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Sample records for animal reservoir hosts

  1. The consequences of reservoir host eradication on disease epidemiology in animal communities

    PubMed Central

    Al-Shorbaji, Farah; Roche, Benjamin; Gozlan, Rodolphe; Britton, Robert; Andreou, Demetra

    2016-01-01

    Non-native species have often been linked with introduction of novel pathogens that spill over into native communities, and the amplification of the prevalence of native parasites. In the case of introduced generalist pathogens, their disease epidemiology in the extant communities remains poorly understood. Here, Sphaerothecum destruens, a generalist fungal-like fish pathogen with bi-modal transmission (direct and environmental) was used to characterise the biological drivers responsible for disease emergence in temperate fish communities. A range of biotic factors relating to both the pathogen and the surrounding host communities were used in a novel susceptible-exposed-infectious-recovered (SEIR) model to test how these factors affected disease epidemiology. These included: (i) pathogen prevalence in an introduced reservoir host (Pseudorasbora parva); (ii) the impact of reservoir host eradication and its timing and (iii) the density of potential hosts in surrounding communities and their connectedness. These were modelled across 23 combinations and indicated that the spill-over of pathogen propagules via environmental transmission resulted in rapid establishment in adjacent fish communities (<1 year). Although disease dynamics were initially driven by environmental transmission in these communities, once sufficient numbers of native hosts were infected, the disease dynamics were driven by intra-species transmission. Subsequent eradication of the introduced host, irrespective of its timing (after one, two or three years), had limited impact on the long-term disease dynamics among local fish communities. These outputs reinforced the importance of rapid detection and eradication of non-native species, in particular when such species are identified as healthy reservoirs of a generalist pathogen. PMID:27165562

  2. The armadillo as an animal model and reservoir host for Mycobacterium leprae.

    PubMed

    Balamayooran, Gayathriy; Pena, Maria; Sharma, Rahul; Truman, Richard W

    2015-01-01

    Apart from humans, armadillos are the only known natural hosts of Mycobacterium leprae. They are well developed as hosts for in vivo propagation of M leprae and are advancing as models for studying the pathogenesis of leprosy and translational research. Armadillos are immunologically intact. They exhibit the full Ridley-Jopling spectrum of histopathologic responses to M leprae and uniquely manifest extensive neurological involvement that closely recapitulates human leprosy. In addition, free-ranging armadillos in some regions are known to harbor a naturally occurring infection with M leprae, and zoonotic transmission between armadillos and humans has been implicated in a large number of new case presentations. We review the role of the armadillo as a model for leprosy and reservoir for human infection.

  3. Mycobacterium bovis: characteristics of wildlife reservoir hosts.

    PubMed

    Palmer, M V

    2013-11-01

    Mycobacterium bovis is the cause of tuberculosis in animals and sometimes humans. Many developed nations have long-standing programmes to eradicate tuberculosis in livestock, principally cattle. As disease prevalence in cattle decreases these efforts are sometimes impeded by passage of M. bovis from wildlife to cattle. In epidemiological terms, disease can persist in some wildlife species, creating disease reservoirs, if the basic reproduction rate (R0) and critical community size (CCS) thresholds are achieved. Recognized wildlife reservoir hosts of M. bovis include the brushtail possum (Trichosurus vulpecula) in New Zealand, European badger (Meles meles) in Great Britain and Ireland, African buffalo (Syncerus caffer) in South Africa, wild boar (Sus scrofa) in the Iberian Peninsula and white-tailed deer (Odocoileus virginianus) in Michigan, USA. The epidemiological concepts of R0 and CCS are related to more tangible disease/pathogen characteristics such as prevalence, pathogen-induced pathology, host behaviour and ecology. An understanding of both epidemiological and disease/pathogen characteristics is necessary to identify wildlife reservoirs of M. bovis. In some cases, there is a single wildlife reservoir host involved in transmission of M. bovis to cattle. Complexity increases, however, in multihost systems where multiple potential reservoir hosts exist. Bovine tuberculosis eradication efforts require elimination of M. bovis transmission between wildlife reservoirs and cattle. For successful eradication identification of true wildlife reservoirs is critical, as disease control efforts are most effective when directed towards true reservoirs.

  4. Leptospira Serovars for Diagnosis of Leptospirosis in Humans and Animals in Africa: Common Leptospira Isolates and Reservoir Hosts

    PubMed Central

    Mgode, Georgies F.; Machang’u, Robert S.; Mhamphi, Ginethon G.; Katakweba, Abdul; Mulungu, Loth S.; Durnez, Lies; Leirs, Herwig; Hartskeerl, Rudy A.; Belmain, Steven R.

    2015-01-01

    The burden of leptospirosis in humans and animals in Africa is higher than that reported from other parts of the world. However, the disease is not routinely diagnosed in the continent. One of major factors limiting diagnosis is the poor availability of live isolates of locally circulating Leptospira serovars for inclusion in the antigen panel of the gold standard microscopic agglutination test (MAT) for detecting antibodies against leptospirosis. To gain insight in Leptospira serovars and their natural hosts occurring in Tanzania, concomitantly enabling the improvement of the MAT by inclusion of fresh local isolates, a total of 52 Leptospira isolates were obtained from fresh urine and kidney homogenates, collected between 1996 and 2006 from small mammals, cattle and pigs. Isolates were identified by serogrouping, cross agglutination absorption test (CAAT), and molecular typing. Common Leptospira serovars with their respective animal hosts were: Sokoine (cattle and rodents); Kenya (rodents and shrews); Mwogolo (rodents); Lora (rodents); Qunjian (rodent); serogroup Grippotyphosa (cattle); and an unknown serogroup from pigs. Inclusion of local serovars particularly serovar Sokoine in MAT revealed a 10-fold increase in leptospirosis prevalence in Tanzania from 1.9% to 16.9% in rodents and 0.26% to 10.75% in humans. This indicates that local serovars are useful for diagnosis of human and animal leptospirosis in Tanzania and other African countries. PMID:26624890

  5. Comparative infectivity of Fasciola hepatica metacercariae from isolates of the main and secondary reservoir animal host species in the Bolivian Altiplano high human endemic region.

    PubMed

    Valero, M A; Mas-Coma, S

    2000-01-01

    Fascioliasis due to Fasciola hepatica (Linnaeus, 1758) is an endemic disease on the Northern Bolivian Altiplano, where human prevalences and intensities are the highest known, sheep and cattle are the main reservoir hosts, and pigs and donkeys the secondary ones. Investigations were carried out to study the viability of metacercariae experimentally obtained from eggs shed by naturally infected Altiplanic sheep, cattle, pigs and donkeys. A total of 157 Wistar rats were infected with doses of 5, 10, 20 and 150 metacercariae. Metacercariae aged for different number of weeks were used to analyse the influence of age on their viability. The number of worms successfully developed in each rat was established by dissection. Results obtained show that metacercarial infectivity is dependent upon storage time, being lower when metacercariae are older. The maximum longevity is 31 weeks using doses of 20 metacercariae per rat and 48 weeks with 150 metacercariae per rat, although in the latter case only a very low percentage of worms is recovered. Age-related infectivity of metacercariae from Altiplanic F. hepatica does not significantly differ from that of the liver fluke in lowlands of other countries. Concerning the influence of the isolate according to host species, results indicate that metacercarial viabilities of pig and donkey isolates are similar to the viabilities of metacercariae of sheep and cattle isolates. Thus, pig and donkey have a high transmission potential capacity concerning this aspect. This fact is of great importance for the control of human and animal fascioliasis in this highly endemic zone.

  6. Reservoir hosts of Leptospira inadai in India.

    PubMed

    Gangadhar, N L; Rajasekhar, M; Smythe, L D; Norris, M A; Symonds, M L; Dohnt, M F

    2000-12-01

    Isolation of Leptospira from the kidneys of Rattus rattus wroughtoni hinton, Rattus rattus rufescens, Bandicota bengalensis and Bandicota indica was attempted in Bangalore in southern India. In total, 296 spirochaetes were isolated from 1,348 kidney cultures (an isolation rate of 22%). A batch of fifty-six isolates from India was identified, based on serological and polymerase chain reaction analysis, of which twenty-three isolates were identified as L. inadai by the World Health Organization/Food and Agriculture Organization Collaborating Centre for Reference and Research on Leptospirosis, in Brisbane. This is the first record of isolation of L. inadai from rodents. The preponderance of L. inadai in four different species of rodents suggests that these animals could be the natural reservoir hosts of L. inadai, and raises a critical question as to the likely impact of this species of Leptospira on the renal carrier status of other Leptospira pathogenic to humans and animals in this part of India. Virulence studies conducted at the University of Trieste in Italy, revealed that isolates of L. inadai from India were moderately or totally serum resistant when subjected to a serum killing test. To establish the possible seroprevalence of this species in the population, the inclusion of L. inadai in the battery of leptospiral antigens used for sero-epidemiological studies is recommended.

  7. Reservoir Host Immune Responses to Emerging Zoonotic Viruses

    PubMed Central

    Mandl, Judith N.; Ahmed, Rafi; Barreiro, Luis B.; Daszak, Peter; Epstein, Jonathan H.; Virgin, Herbert W.; Feinberg, Mark B.

    2015-01-01

    Zoonotic viruses, such as HIV, Ebola virus, coronaviruses, influenza A viruses, hantaviruses, or henipaviruses, can result in profound pathology in humans. In contrast, populations of the reservoir hosts of zoonotic pathogens often appear to tolerate these infections with little evidence of disease. Why are viruses more dangerous in one species than another? Immunological studies investigating quantitative and qualitative differences in the host-virus equilibrium in animal reservoirs will be key to answering this question, informing new approaches for treating and preventing zoonotic diseases. Integrating an understanding of host immune responses with epidemiological, ecological, and evolutionary insights into viral emergence will shed light on mechanisms that minimize fitness costs associated with viral infection, facilitate transmission to other hosts, and underlie the association of specific reservoir hosts with multiple emerging viruses. Reservoir host studies provide a rich opportunity for elucidating fundamental immunological processes and their underlying genetic basis, in the context of distinct physiological and metabolic constraints that contribute to host resistance and disease tolerance. PMID:25533784

  8. Cowpox: reservoir hosts and geographic range.

    PubMed Central

    Chantrey, J.; Meyer, H.; Baxby, D.; Begon, M.; Bown, K. J.; Hazel, S. M.; Jones, T.; Montgomery, W. I.; Bennett, M.

    1999-01-01

    It is generally accepted that the reservoir hosts of cowpox virus are wild rodents, although direct evidence for this is lacking for much of the virus's geographic range. Here, through a combination of serology and PCR, we demonstrate conclusively that the main hosts in Great Britain are bank voles, wood mice and short-tailed field voles. However, we also suggest that wood mice may not be able to maintain infection alone, explaining the absence of cowpox from Ireland where voles are generally not found. Infection in wild rodents varies seasonally, and this variation probably underlies the marked seasonal incidence of infection in accidental hosts such as humans and domestic cats. PMID:10459650

  9. Detection of urinary biomarkers in reservoir hosts of Leptospirosis by capillary electrophoresis mass spectrometry

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Pathogenic leptospires colonize the renal tubules of reservoir hosts of infection and are excreted via urine into the environment. Reservoir hosts include a wide range of domestic and wild animal species and include cattle, dogs and rats which can persistently excrete large numbers of pathogenic lep...

  10. [Animal reservoirs of human virulent microsporidian species].

    PubMed

    Słodkowicz-Kowalska, Anna

    2009-01-01

    The main objective of the present study was to determined the occurrence of Encephalitozoon intestinalis, E. hellem, E. cuniculi, and Enterocytozoon bieneusi in Poland in animal faecal using the FISH (Fluorescent In Situ Hybridization) and multiplex FISH techniques. Additional objectives included: (1) identification of animal hosts of microsporidia that are infectious to humans amongst free-ranging, captive, livestock and domestic animals; (2) a molecular analysis of randomly selected parasite isolates and determination of their zoonotic potential; (3) evaluation of the role of animals in the dissemination of microsporidia spores in the environment, and an estimation of the potential risk of infection for other animals and humans. A total of 1340 faecal samples collected from 178 species of animals were examined using conventional staining (chromotrope-2R and calcofluor white M2R staining) and molecular techniques (FISH and multiplex FISH techniques). Microsporidian spores were detected in 33 faecal samples (2.5%) obtained from 17 animal species. Microsporidia were demonstrated more often in birds (6.1%) than in mammals (0.7%); the difference was statistically significant (p < 0.00001). In addition, the prevalence of microsporidian infections in waterfowl was significantly higher than the prevalence of microsporidian infections in other animals (p < 0.03). Animal reservoirs of human infectious microsporidia were disclosed in six of 38 sites where faecal samples were taken from animals. Three species of human virulent microsporidia were identified in animals. Spores of E. hellem were found in 25 faecal samples (1.9%) taken from 12 bird species (6 zoo bird species, 4 free-ranging bird species, 2 livestock bird species). Spores of E. intestinalis were identified in five faecal samples (0.4%) taken from two livestock bird species and two zoo mammal species. In turn, E. bieneusi spores were detected only in three faecal samples (0.2%) taken from three zoo mammal species

  11. Vector and reservoir host of a case of human Brugia pahangi infection in Selangor, peninsular Malaysia.

    PubMed

    Muslim, A; Fong, M Y; Mahmud, R; Sivanandam, S

    2013-12-01

    A case of human eye infection caused by Brugia pahangi was reported in 2010 in a semi rural village in Selangor, peninsular Malaysia. Our report here reveals results of investigation on the vector and animal host for the transmission of the infection. We conducted entomological survey and cat blood examination in the vicinity of the patient's home. The mosquito species Armigeres subalbatus was incriminated as the vector, whereas cat served as the reservoir host.

  12. Does reservoir host mortality enhance transmission of West Nile virus?

    PubMed Central

    Foppa, Ivo M; Spielman, Andrew

    2007-01-01

    Background Since its 1999 emergence in New York City, West Nile virus (WNV) has become the most important and widespread cause of mosquito-transmitted disease in North America. Its sweeping spread from the Atlantic to the Pacific coast was accompanied by widespread mortality among wild birds, especially corvids. Only sporadic avian mortality had previously been associated with this infection in the Old World. Here, we examine the possibility that reservoir host mortality may intensify transmission, both by concentrating vector mosquitoes on remaining hosts and by preventing the accumulation of "herd immunity". Results Inspection of the Ross-Macdonald expression of the basic reproductive number (R0) suggests that this quantity may increase with reservoir host mortality. Computer simulation confirms this finding and indicates that the level of virulence is positively associated with the numbers of infectious mosquitoes by the end of the epizootic. The presence of reservoir incompetent hosts in even moderate numbers largely eliminated the transmission-enhancing effect of host mortality. Local host die-off may prevent mosquitoes to "waste" infectious blood meals on immune host and may thus facilitate perpetuation and spread of transmission. Conclusion Under certain conditions, host mortality may enhance transmission of WNV and similarly maintained arboviruses and thus facilitate their emergence and spread. The validity of the assumptions upon which this argument is built need to be empirically examined. PMID:17498307

  13. Standardised animal models of host microbial mutualism

    PubMed Central

    Macpherson, A J; McCoy, K D

    2015-01-01

    An appreciation of the importance of interactions between microbes and multicellular organisms is currently driving research in biology and biomedicine. Many human diseases involve interactions between the host and the microbiota, so investigating the mechanisms involved is important for human health. Although microbial ecology measurements capture considerable diversity of the communities between individuals, this diversity is highly problematic for reproducible experimental animal models that seek to establish the mechanistic basis for interactions within the overall host-microbial superorganism. Conflicting experimental results may be explained away through unknown differences in the microbiota composition between vivaria or between the microenvironment of different isolated cages. In this position paper, we propose standardised criteria for stabilised and defined experimental animal microbiotas to generate reproducible models of human disease that are suitable for systematic experimentation and are reproducible across different institutions. PMID:25492472

  14. Bats: Important Reservoir Hosts of Emerging Viruses

    PubMed Central

    Calisher, Charles H.; Childs, James E.; Field, Hume E.; Holmes, Kathryn V.; Schountz, Tony

    2006-01-01

    Bats (order Chiroptera, suborders Megachiroptera [“flying foxes”] and Microchiroptera) are abundant, diverse, and geographically widespread. These mammals provide us with resources, but their importance is minimized and many of their populations and species are at risk, even threatened or endangered. Some of their characteristics (food choices, colonial or solitary nature, population structure, ability to fly, seasonal migration and daily movement patterns, torpor and hibernation, life span, roosting behaviors, ability to echolocate, virus susceptibility) make them exquisitely suitable hosts of viruses and other disease agents. Bats of certain species are well recognized as being capable of transmitting rabies virus, but recent observations of outbreaks and epidemics of newly recognized human and livestock diseases caused by viruses transmitted by various megachiropteran and microchiropteran bats have drawn attention anew to these remarkable mammals. This paper summarizes information regarding chiropteran characteristics and information regarding 66 viruses that have been isolated from bats. From these summaries, it is clear that we do not know enough about bat biology; we are doing too little in terms of bat conservation; and there remain a multitude of questions regarding the role of bats in disease emergence. PMID:16847084

  15. Reservoir host competence and the role of domestic and commensal hosts in the transmission of Trypanosoma cruzi.

    PubMed

    Gürtler, Ricardo E; Cardinal, M V

    2015-11-01

    We review the epidemiological role of domestic and commensal hosts of Trypanosoma cruzi using a quantitative approach, and compiled >400 reports on their natural infection. We link the theory underlying simple mathematical models of vector-borne parasite transmission to the types of evidence used for reservoir host identification: mean duration of infectious life; host infection and infectiousness; and host-vector contact. The infectiousness of dogs or cats most frequently exceeded that of humans. The host-feeding patterns of major vectors showed wide variability among and within triatomine species related to their opportunistic behavior and variable ecological, biological and social contexts. The evidence shows that dogs, cats, commensal rodents and domesticated guinea pigs are able to maintain T. cruzi in the absence of any other host species. They play key roles as amplifying hosts and sources of T. cruzi in many (peri)domestic transmission cycles covering a broad diversity of ecoregions, ecotopes and triatomine species: no other domestic animal plays that role. Dogs comply with the desirable attributes of natural sentinels and sometimes were a point of entry of sylvatic parasite strains. The controversies on the role of cats and other hosts illustrate the issues that hamper assessing the relative importance of reservoir hosts on the basis of fragmentary evidence. We provide various study cases of how eco-epidemiological and genetic-marker evidence helped to unravel transmission cycles and identify the implicated hosts. Keeping dogs, cats and rodents out of human sleeping quarters and reducing their exposure to triatomine bugs are predicted to strongly reduce transmission risks.

  16. Animal genomics in natural reservoirs of infectious diseases.

    PubMed

    Cowled, C; Wang, L-F

    2016-04-01

    Natural virus reservoirs such as wild bats, birds, rodents and non-human primates are generally non-model organisms that have, until recently, presented limited opportunities for in-depth study. Next-generation sequencing provides a way to partially circumvent this limitation, since the methods required for data acquisition and analysis are largely species-independent. Comparative genomics and other 'omics' provide new opportunities to study the structure and function of various biological systems of wild species that are otherwise out of reach. Genomes of natural reservoir hosts can help to identify dominant pathways of virus-host interaction and to reveal differences between susceptible and resistant organisms, populations and species. This is of great scientific interest and may also provide a resource for the rational design of treatments for viral diseases in humans and livestock. In this way, we will 'learn from nature' and one day apply this knowledge to create disease-resistant livestock or develop novel therapeutic and prevention strategies. Reservoir host genomics will also open up possibilities for developing novel vaccines for wildlife, aid in the development of new diagnostic platforms, and have broad implications for developmental and evolutionary biology. In this review, the authors focus on natural reservoir hosts of viral pathogens, although most of the discussion points should be equally applicable to natural reservoirs of pathogenic bacteria, fungi or other parasites.

  17. ANIMAL RESERVOIRS, VECTORS, AND TRANSMISSION OF MICROSPORIDIA

    EPA Science Inventory

    Fourteen species of microsporidia have been identified as opportunistic or emerging pathogens of humans. Several genotypes of Enterocytozoon bieneusi, the most frequently diagnosed species in humans, have been identified in Europe in farm and companion animals including pigs, cat...

  18. Ticks infesting wild and domestic animals and humans of Sri Lanka with new host records.

    PubMed

    Liyanaarachchi, D R; Rajakaruna, R S; Dikkumbura, A W; Rajapakse, R P V J

    2015-02-01

    An island-wide collection of tick species infesting humans, domesticated and wild animals and questing ticks in domestic and peridomestic environments was carried out during 2009-2011. A total of 30,461 ticks were collected from 30 different hosts and free living stages from the ground. The collection consisted of 22 tick species from 30 different hosts recording 12 tick species from humans, 19 from domesticated animals and 21 from wild animals, with a total of 97 new host records. The most common tick species on humans were Dermacentor auratus and Amblyomma testudinairum, while Haemaphysalis intermedia, Rhipicephalus microplus and Rhipicephalus sanguineus were common in domesticated and wild animals sharing 20 host species. Among the questing ticks, immature D. auratus was the most abundant. Humans and domesticated animals were mostly infested by the nymphal stages while adult ticks were found on wild animals. High number of new host records could be due to domestic animals picking tick species from wildlife and vise versa at the human/animal interface. Habitat destruction due to forest fragmentation has lead to wild animals roaming in urban and semi-urban neighbourhoods increasing the interactions of wild animals with domesticated animals. Wild animals play a significant role as a reservoir of many tick borne infections which can easily be spread to domesticated animals and then to humans via tick infestations. Data in this paper are useful for those interested in tick infesting wild and domestic animals and humans in describing the zoonotic potential of tick borne infections.

  19. Hantavirus reservoir hosts associated with peridomestic habitats in Argentina.

    PubMed Central

    Calderón, G.; Pini, N.; Bolpe, J.; Levis, S.; Mills, J.; Segura, E.; Guthmann, N.; Cantoni, G.; Becker, J.; Fonollat, A.; Ripoll, C.; Bortman, M.; Benedetti, R.; Enria, D.

    1999-01-01

    Five species of sigmodontine rodents have been identified in Argentina as the putative reservoirs of six circulating hantavirus genotypes. Two species of Oligoryzomys are associated with the genotypes causing hantavirus pulmonary syndrome, Oligoryzomys flavescens for Lechiguanas and O. longicaudatus for Andes and Oran genotypes. Reports of human cases of hantavirus pulmonary syndrome prompted rodent trapping (2,299 rodents of 32 species during 27,780 trap nights) at potential exposure sites in three disease-endemic areas. Antibody reactive to Sin Nombre virus was found in six species, including the known hantavirus reservoir species. Risk for peridomestic exposure to host species that carry recognized human pathogens was high in all three major disease-endemic areas. PMID:10603213

  20. Zoonotic Hepatitis E Virus: Classification, Animal Reservoirs and Transmission Routes

    PubMed Central

    Doceul, Virginie; Bagdassarian, Eugénie; Demange, Antonin; Pavio, Nicole

    2016-01-01

    During the past ten years, several new hepatitis E viruses (HEVs) have been identified in various animal species. In parallel, the number of reports of autochthonous hepatitis E in Western countries has increased as well, raising the question of what role these possible animal reservoirs play in human infections. The aim of this review is to present the recent discoveries of animal HEVs and their classification within the Hepeviridae family, their zoonotic and species barrier crossing potential, and possible use as models to study hepatitis E pathogenesis. Lastly, this review describes the transmission pathways identified from animal sources. PMID:27706110

  1. The Egyptian mongoose, Herpestes ichneumon, is a possible reservoir host of visceral leishmaniasis in eastern Sudan.

    PubMed

    Elnaiem, D A; Hassan, M M; Maingon, R; Nureldin, G H; Mekawi, A M; Miles, M; Ward, R D

    2001-05-01

    Investigations were made on possible reservoir hosts of Leishmania donovani in 2 zoonotic foci of visceral leishmaniasis (VL) in Dinder National Park (DNP) and the peri-domestic habitats of adjacent villages of eastern Sudan. Animals were captured, in November 1997-1998 and April-May 1999 and examined for L. donovani infection using light microscopy and 2 sensitive Polymerase Chain Reaction (PCR) systems. Microscopy and PCR investigations were also used to determine the infection rates of L. donovani in Phlebotomus orientalis captured from the uninhabited site of DNP. Infections of L. donovani were detected in 2 out of 14 Egyptian mongooses (Herpestes ichneumon), 1 out of 168 Arviconthus niloticus and 1 out of 8 Mastomys natalensis. Samples from 68 other animals captured from the study area were all negative for the infection. Active zoonotic transmission of L. donovani at the time of animal sampling in the uninhabited site of DNP was demonstrated by finding the parasite in 3.4% (7 out of 184) and 3.2% (5 out of 157) of flies collected in March 1998 and May 1999, respectively. We suggest that the Egyptian mongoose is a possible reservoir host of L. donovani. The importance of other animals in maintaining the infection is also discussed.

  2. Animal reservoirs for visceral leishmaniasis in densely populated urban areas.

    PubMed

    Diniz, Soraia A; Silva, Fabiana L; Carvalho Neta, Alcina C; Bueno, Regina; Guerra, Rita M S N C; Abreu-Silva, Ana L; Santos, Renato L

    2008-02-01

    Leishmaniasis is a zoonotic disease of major public health and veterinary importance, affecting 88 countries with up to 2 million cases per year. This review emphasizes the animal reservoirs and spreading of visceral leishmaniasis (VL) in urban areas, particularly in two Brazilian metropolitan areas, namely São Luis and Belo Horizonte, where the disease has become endemic in the past few years. Urbanization of visceral leishmaniasis in Brazil during the last decades has created favorable epidemiological conditions for maintenance of the disease, with dense human populations sharing a tropical environment with abundant populations of the mammalian reservoir and the invertebrate vector, facilitating transmission of the disease.

  3. Sensitivity of Lyme Borreliosis Spirochetes to Serum Complement of Regular Zoo Animals: Potential Reservoir Competence of Some Exotic Vertebrates.

    PubMed

    Ticha, Lucie; Golovchenko, Maryna; Oliver, James H; Grubhoffer, Libor; Rudenko, Nataliia

    2016-01-01

    Reaction of vertebrate serum complement with different Borrelia burgdorferi sensu lato species is used as a basis in determining reservoir hosts among domesticated and wild animals. Borrelia burgdorferi sensu stricto, Borrelia garinii, and Borrelia afzelii were tested for their sensitivity to sera of exotic vertebrate species housed in five zoos located in the Czech Republic. We confirmed that different Borrelia species have different sensitivity to host serum. We found that tolerance to Borrelia infection possessed by hosts might differ among individuals of the same genera or species and is not affected by host age or sex. Of all zoo animals included in our study, carnivores demonstrated the highest apparent reservoir competency for Lyme borreliosis spirochetes. We showed that selected exotic ungulate species are tolerant to Borrelia infection. For the first time we showed the high tolerance of Siamese crocodile to Borrelia as compared to the other studied reptile species. While exotic vertebrates present a limited risk to the European human population as reservoirs for the causative agents of Lyme borreliosis, cases of incidental spillover infection could lead to successful replication of the pathogens in a new host, changing the status of selected exotic species and their role in pathogen emergence or maintenance. The question if being tolerant to pathogen means to be a competent reservoir host still needs an answer, simply because the majority of exotic animals might never be exposed to spirochetes in their natural environment.

  4. Wild animals as reservoirs of infectious diseases in the UK.

    PubMed

    Simpson, V R

    2002-03-01

    This review aims to illustrate the extent to which wildlife act as reservoirs of infectious agents that cause disease in domestic stock, pet and captive animals and humans. More than 40 agents are described. In the case of some of these, e.g. Cryptosporidium spp., Escherichia coli O157 and malignant catarrhal fever, the current evidence is that wildlife either does not act as a reservoir or is of limited importance. However, in the case of many important diseases, including bovine tuberculosis, Weil's disease, Lyme disease, avian influenza, duck virus enteritis and louping ill, wild animals are considered to be the principal source of infection. Wildlife may be involved in the epidemiology of other major diseases, such as neosporosis, Johne's disease, mucosal disease and foot and mouth disease, but further studies are needed. The UK would benefit from a more positive approach to the study of wildlife and the infections they harbour.

  5. Implications of Heterogeneous Biting Exposure and Animal Hosts on Trypanosomiasis brucei gambiense Transmission and Control

    PubMed Central

    Stone, Chris M.; Chitnis, Nakul

    2015-01-01

    The gambiense form of sleeping sickness is a neglected tropical disease, which is presumed to be anthroponotic. However, the parasite persists in human populations at levels of considerable rarity and as such the existence of animal reservoirs has been posited. Clarifying the impact of animal host reservoirs on the feasibility of interrupting sleeping sickness transmission through interventions is a matter of urgency. We developed a mathematical model allowing for heterogeneous exposure of humans to tsetse, with animal populations that differed in their ability to transmit infections, to investigate the effectiveness of two established techniques, screening and treatment of at-risk populations, and vector control. Importantly, under both assumptions, an integrated approach of human screening and vector control was supported in high transmission areas. However, increasing the intensity of vector control was more likely to eliminate transmission, while increasing the intensity of human screening reduced the time to elimination. Non-human animal hosts played important, but different roles in HAT transmission, depending on whether or not they contributed as reservoirs. If they did not serve as reservoirs, sensitivity analyses suggested their attractiveness may instead function as a sink for tsetse bites. These outcomes highlight the importance of understanding the ecological and environmental context of sleeping sickness in optimizing integrated interventions, particularly for moderate and low transmission intensity settings. PMID:26426854

  6. Wild fauna as a probable animal reservoir for Trypanosoma brucei gambiense in Cameroon.

    PubMed

    Njiokou, F; Laveissière, C; Simo, G; Nkinin, S; Grébaut, P; Cuny, G; Herder, S

    2006-03-01

    In order to study the existence of a wild animal reservoir for Trypanosoma brucei gambiense in South Cameroon, blood was collected from wild animals in three human African trypanosomiasis foci and from a nonendemic control area. The 1142 wild animals sampled belonged to 36 different species pertaining to eight orders (407 primates, 347 artiodactyls, 265 rodents, 54 pangolins, 53 carnivores, 11 saurians and crocodilians, and five hyraxes). QBC and KIVI tests detected trypanosomes on 1.7% (13/762) and 18.4% (43/234) of animals examined, respectively. Using specific primers, T. brucei non-gambiense group 1 DNA was detected on 56 animals (4.9%). This infection rate was 5.3% in the endemic zone and 3.8% in the control zone. Of the 832 animals of the endemic zone, PCR revealed T. b. gambiense group 1 DNA in 18 (2.2%). These hosts included two rodents, two artiodactyls, two carnivores and two primates. T. b. gambiense group 1 was absent from animals from the nonendemic zone. A decrease in the prevalence of T. b. gambiense group 1 was observed in wild animals from the Bipindi sleeping sickness focus after a medical survey and vector control in this area. The epidemiological implications of these findings remain to be determined with further investigations.

  7. Zoonotic hepatitis E: animal reservoirs and emerging risks.

    PubMed

    Pavio, Nicole; Meng, Xiang-Jin; Renou, Christophe

    2010-01-01

    Hepatitis E virus (HEV) is responsible for enterically-transmitted acute hepatitis in humans with two distinct epidemiological patterns. In endemic regions, large waterborne epidemics with thousands of people affected have been observed, and, in contrast, in non-endemic regions, sporadic cases have been described. Although contaminated water has been well documented as the source of infection in endemic regions, the modes of transmission in non-endemic regions are much less known. HEV is a single-strand, positive-sense RNA virus which is classified in the Hepeviridae family with at least four known main genotypes (1-4) of mammalian HEV and one avian HEV. HEV is unique among the known hepatitis viruses, in which it has an animal reservoir. In contrast to humans, swine and other mammalian animal species infected by HEV generally remain asymptomatic, whereas chickens infected by avian HEV may develop a disease known as Hepatitis-Splenomegaly syndrome. HEV genotypes 1 and 2 are found exclusively in humans while genotypes 3 and 4 are found both in humans and other mammals. Several lines of evidence indicate that, in some cases involving HEV genotypes 3 and 4, animal to human transmissions occur. Furthermore, individuals with direct contact with animals are at higher risk of HEV infection. Cross-species infections with HEV genotypes 3 and 4 have been demonstrated experimentally. However, not all sources of human infections have been identified thus far and in many cases, the origin of HEV infection in humans remains unknown.

  8. Hepatitis E virus: animal reservoirs and zoonotic risk.

    PubMed

    Meng, X J

    2010-01-27

    Hepatitis E virus (HEV) is a small, non-enveloped, single-strand, positive-sense RNA virus of approximately 7.2kb in size. HEV is classified in the family Hepeviridae consisting of four recognized major genotypes that infect humans and other animals. Genotypes 1 and 2 HEV are restricted to humans and often associated with large outbreaks and epidemics in developing countries with poor sanitation conditions, whereas genotypes 3 and 4 HEV infect humans, pigs and other animal species and are responsible for sporadic cases of hepatitis E in both developing and industrialized countries. The avian HEV associated with Hepatitis-Splenomegaly syndrome in chickens is genetically and antigenically related to mammalian HEV, and likely represents a new genus in the family. There exist three open reading frames in HEV genome: ORF1 encodes non-structural proteins, ORF2 encodes the capsid protein, and the ORF3 encodes a small phosphoprotein. ORF2 and ORF3 are translated from a single bicistronic mRNA, and overlap each other but neither overlaps ORF1. Due to the lack of an efficient cell culture system and a practical animal model for HEV, the mechanisms of HEV replication and pathogenesis are poorly understood. The recent identification and characterization of animal strains of HEV from pigs and chickens and the demonstrated ability of cross-species infection by these animal strains raise potential public health concerns for zoonotic HEV transmission. It has been shown that the genotypes 3 and 4 HEV strains from pigs can infect humans, and vice versa. Accumulating evidence indicated that hepatitis E is a zoonotic disease, and swine and perhaps other animal species are reservoirs for HEV. A vaccine against HEV is not yet available.

  9. Leishmania infantum in wild rodents: reservoirs or just irrelevant incidental hosts?

    PubMed

    Navea-Pérez, H M; Díaz-Sáez, V; Corpas-López, V; Merino-Espinosa, G; Morillas-Márquez, F; Martín-Sánchez, J

    2015-06-01

    Wild rodents constitute a very large biomass of potential reservoirs for Leishmania spp. Therefore, an epidemiological study was carried out in a well-known focus of canine leishmaniasis from southern Spain, with the objective of detecting and characterizing Leishmania infantum infection in wild rodents. Blood, liver, spleen, bone marrow, and skin from 37 rodents (24 Apodemus sylvaticus, 9 Rattus rattus, and 4 Mus musculus) were analyzed by optical microscopy, culture, and two different polymerase chain reactions. L. infantum DNA was found in 27% (10 out of 37) of the trapped rodents, in a variety of tissues: bone marrow, spleen, or healthy skin (ear lobe). High prevalences of L. infantum infection were found in the three investigated rodent species. The presence of other trypanosomatids was also evidenced. These rodent species are abundant, widely distributed in Europe, and have a long enough lifespan to overcome the low sandfly activity season. They live in a suitable habitat for sandflies and serve as blood sources for these insects, which can become infected when induced to feed on Leishmania-infected animals. Whether they are reservoirs or just irrelevant incidental hosts, it is clear that the epidemiology of L. infantum is more complex than previously thought, and so is its control. The classic epidemiological cycle dog-sandfly-human is turning into a network of animal species that collaborate with the dog in the maintenance of the parasite under natural conditions and probably showing local differences.

  10. Wild animals as reservoirs of Anaplasma phagocytophilum for humans

    PubMed

    Dzięgiel, Beata; Adaszek, Łukasz; Winiarczyk, Stanisław

    Anaplasma phagocytophilum is a tick-transmitted obligate-intracellular gram-negative bacteria that causes emerging human zoonosis. A. phagocytophilum is transmitted by Ixodid ticks. Recent studies suggest that wild animals may be reservoirs of A. phagocytophilum for humans. The organism infects and survives within neutrophils. The infection diagnosis is based on the detection of morulae within granulocytes of peripheral blood, results of serological tests and detection of the DNA of A. phagocytophilum using specific polymerase chain reaction assays (PCR). A. phagocytophilum in most cases is transmitted to people by tick bites, but sometimes direct contact with infected blood may cause human granulocytic anaplasmosis (HGA). The possibility of infection should be taken into consideration at each occurrence of heavy disease symptoms after people come into contact with ticks.

  11. More novel hantaviruses and diversifying reservoir hosts--time for development of reservoir-derived cell culture models?

    PubMed

    Eckerle, Isabella; Lenk, Matthias; Ulrich, Rainer G

    2014-02-26

    Due to novel, improved and high-throughput detection methods, there is a plethora of newly identified viruses within the genus Hantavirus. Furthermore, reservoir host species are increasingly recognized besides representatives of the order Rodentia, now including members of the mammalian orders Soricomorpha/Eulipotyphla and Chiroptera. Despite the great interest created by emerging zoonotic viruses, there is still a gross lack of in vitro models, which reflect the exclusive host adaptation of most zoonotic viruses. The usually narrow host range and genetic diversity of hantaviruses make them an exciting candidate for studying virus-host interactions on a cellular level. To do so, well-characterized reservoir cell lines covering a wide range of bat, insectivore and rodent species are essential. Most currently available cell culture models display a heterologous virus-host relationship and are therefore only of limited value. Here, we review the recently established approaches to generate reservoir-derived cell culture models for the in vitro study of virus-host interactions. These successfully used model systems almost exclusively originate from bats and bat-borne viruses other than hantaviruses. Therefore we propose a parallel approach for research on rodent- and insectivore-borne hantaviruses, taking the generation of novel rodent and insectivore cell lines from wildlife species into account. These cell lines would be also valuable for studies on further rodent-borne viruses, such as orthopox- and arenaviruses.

  12. Animal Reservoirs of Zoonotic Tungiasis in Endemic Rural Villages of Uganda

    PubMed Central

    Mutebi, Francis; Krücken, Jürgen; Feldmeier, Hermann; Waiswa, Charles; Mencke, Norbert; Sentongo, Elizabeth; von Samson-Himmelstjerna, Georg

    2015-01-01

    Background Animal tungiasis is believed to increase the prevalence and parasite burden in humans. Animal reservoirs of Tunga penetrans differ among endemic areas and their role in the epidemiology of tungiasis had never been investigated in Uganda. Methods and Findings To identify the major animal reservoirs of Tunga penetrans and their relative importance in the transmission of tungiasis in Uganda, a cross sectional study was conducted in animal rearing households in 10 endemic villages in Bugiri District. T. penetrans infections were detected in pigs, dogs, goats and a cat. The prevalences of households with tungiasis ranged from 0% to 71.4% (median 22.2) for animals and from 5 to 71.4% (median 27.8%) for humans. The prevalence of human tungiasis also varied among the population of the villages (median 7%, range 1.3–37.3%). Pig infections had the widest distribution (nine out of 10 villages) and highest prevalence (median 16.2%, range 0–64.1%). Pigs also had a higher number of embedded sand fleas than all other species combined (p<0.0001). Dog tungiasis occurred in five out of 10 villages with low prevalences (median of 2%, range 0–26.9%). Only two goats and a single cat had tungiasis. Prevalences of animal and human tungiasis correlated at both village (rho = 0.89, p = 0.0005) and household (rho = 0.4, p<0.0001) levels. The median number of lesions in household animals correlated with the median intensity of infection in children three to eight years of age (rho = 0.47, p<0.0001). Animal tungiasis increased the odds of occurrence of human cases in households six fold (OR = 6.1, 95% CI 3.3–11.4, p<0.0001). Conclusion Animal and human tungiasis were closely associated and pigs were identified as the most important animal hosts of T. penetrans. Effective tungiasis control should follow One Health principles and integrate ectoparasites control in animals. PMID:26473360

  13. Reservoir-host amplification of disease impact in an endangered amphibian.

    PubMed

    Scheele, Ben C; Hunter, David A; Brannelly, Laura A; Skerratt, Lee F; Driscoll, Don A

    2016-09-05

    Emerging wildlife pathogens are an increasing threat to biodiversity. One of the most serious wildlife diseases is chytridiomycosis, caused by the fungal pathogen, Batrachochytrium dendrobatidis (Bd), which has been documented in over 500 amphibian species. Amphibians vary greatly in their susceptibility to Bd; some species tolerate infection, whereas others experience rapid mortality. Reservoir hosts-species that carry infection while maintaining high abundance but are rarely killed by disease-can increase extinction risk in highly susceptible, sympatric species. However, whether reservoir hosts amplify Bd in declining amphibian species has not been examined. We investigated the role of reservoir hosts in the decline of the threatened northern corroboree frog (Pseudophryne pengilleyi) in an amphibian community in southeastern Australia. In the laboratory, we characterized the response of a potential reservoir host, the (nondeclining) common eastern froglet (Crinia signifera), to Bd infection. In the field, we conducted frog abundance surveys and Bd sampling for both P. pengilleyi and C. signifera. We built multinomial logistic regression models to test whether Crinia signifera and environmental factors were associated with P. pengilleyi decline. C. signifera was a reservoir host for Bd. In the laboratory, many individuals maintained intense infections (>1000 zoospore equivalents) over 12 weeks without mortality, and 79% of individuals sampled in the wild also carried infections. The presence of C. signifera at a site was strongly associated with increased Bd prevalence in sympatric P. pengilleyi. Consistent with disease amplification by a reservoir host, P. pengilleyi declined at sites with high C. signifera abundance. Our results suggest that when reservoir hosts are present, population declines of susceptible species may continue long after the initial emergence of Bd, highlighting an urgent need to assess extinction risk in remnant populations of other declined

  14. Sensitivity of Borrelia genospecies to serum complement from different animals and human: a host-pathogen relationship.

    PubMed

    Bhide, Mangesh R; Travnicek, Milan; Levkutova, Maria; Curlik, Jan; Revajova, Viera; Levkut, Mikulas

    2005-02-01

    Different Borrelia species and serotypes were tested for their sensitivity to serum complement from various animals and human. Complement-mediated Borrelia killing in cattle, European bison and deer was higher irrespective of the Borrelia species whereas in other animals and human it was intermediate and Borrelia species-dependent. Activation of the alternative complement pathway by particular Borrelia strain was in correlation with its sensitivity or resistance. These results support the incompetent reservoir nature of cattle, European bison, red, roe and fallow deer, at the same time present the probable reservoir nature of mouflon, dog, wolf, cat and lynx. In short, this study reviews Borrelia-host relationship and its relevance in reservoir competence nature of animals.

  15. [Bats and other reservoir hosts of Filoviridae. Danger of epidemic on the African continent?--a deductive literature analysis].

    PubMed

    Laminger, Felix; Prinz, Armin

    2010-10-01

    Ebola and Marburg virus, forming the Filoviridae family, cause hemorrhagic fever in countries of sub-Saharan Africa. These viral diseases are characterized by a sudden epidemic occurrence as well as a high lethality. Even though a reservoir host has not been approved yet, literature indicates the order of bats (Chiroptera) as a potential reservoir host. Significant references lead to a delineation of a hypothetical ecosystem of Filoviridae including Chiroptera. IgG-specific Ebola-Zaire antibodies were detected in Hammer-headed Bats (Hypsignathus monstrosus), Epauletted Fruit Bats (Epomops franqueti), and Little Collared Fruit Bats (Myonycteris torquata) during Ebola outbreaks between 2001 and 2005 in Gabon and the Republic of the Congo. The discovery of IgG-specific-Marburg virus antibodies and virus-specific ribonucleic acid in Egyptian Fruit Bats (Rousettus aegyptiacus) provided further indication for the exploration of the reservoir host. In 2007, the Marburg virus isolation could for the first time be accomplished directly from apparently healthy and naturally infected Egyptian Fruit Bats (Rousettus aegyptiacus) in Kitaka Mine (Uganda). Risk groups can be defined through chronological reprocessing and interpretation of existing epidemic-outbreaks on the African continent and the search for infection reasons of the index cases. The following risk factors for an infection with Ebola or Marburg virus must be put into consideration: Contact with and consumption of wild animal carcasses, sightseeing in caves as well as work in mines. The focus of this review is the demonstration of risk profiles and their exposure to Chiroptera and other potential reservoir hosts.

  16. Reservoirs and alternate hosts for pathogens of commercially important crustaceans: a review.

    PubMed

    Small, Hamish J; Pagenkopp, Katrina M

    2011-01-01

    There is a considerable body of literature describing the causative agents of many diseases of crustaceans. Given that many of these crustaceans support commercially important fisheries, it is somewhat surprising that comparatively little information is available regarding the natural transmission pathways and reservoirs of many of the disease-causing agents. In this paper we review what is known about reservoirs and alternate hosts for several important diseases of commercially important crustaceans and provide recommendations on future areas of research.

  17. Interaction of Bovine Peripheral Blood Polymorphonuclear Cells and Leptospira Species; Innate Responses in the Natural Bovine Reservoir Host

    PubMed Central

    Wilson-Welder, Jennifer H.; Frank, Ami T.; Hornsby, Richard L.; Olsen, Steven C.; Alt, David P.

    2016-01-01

    Cattle are the reservoir hosts of Leptospira borgpetersenii serovar Hardjo, and can also be reservoir hosts of other Leptospira species such as L. kirschneri, and Leptospira interrogans. As a reservoir host, cattle shed Leptospira, infecting other animals, including humans. Previous studies with human and murine neutrophils have shown activation of neutrophil extracellular trap or NET formation, and upregulation of inflammatory mediators by neutrophils in the presence of Leptospira. Humans, companion animals and most widely studied models of Leptospirosis are of acute infection, hallmarked by systemic inflammatory response, neutrophilia, and septicemia. In contrast, cattle exhibit chronic infection with few outward clinical signs aside from reproductive failure. Taking into consideration that there is host species variation in innate immunity, especially in pathogen recognition and response, the interaction of bovine peripheral blood polymorphonuclear cells (PMNs) and several Leptospira strains was evaluated. Studies including bovine-adapted strains, human pathogen strains, a saprophyte and inactivated organisms. Incubation of PMNs with Leptospira did induce slight activation of neutrophil NETs, greater than unstimulated cells but less than the quantity from E. coli P4 stimulated PMNs. Very low but significant from non-stimulated, levels of reactive oxygen peroxides were produced in the presence of all Leptospira strains and E. coli P4. Similarly, significant levels of reactive nitrogen intermediaries (NO2) was produced from PMNs when incubated with the Leptospira strains and greater quantities in the presence of E. coli P4. PMNs incubated with Leptospira induced RNA transcripts of IL-1β, MIP-1α, and TNF-α, with greater amounts induced by live organisms when compared to heat-inactivated leptospires. Transcript for inflammatory cytokine IL-8 was also induced, at similar levels regardless of Leptospira strain or viability. However, incubation of Leptospira strains

  18. Role of the domestic dog as a reservoir host of Leishmania donovani in eastern Sudan

    PubMed Central

    Hassan, Mo'awia M; Osman, Omran F; El-Raba'a, Fathi MA; Schallig, Henk DFH; Elnaiem, Dia-Eldin A

    2009-01-01

    Background The study aims to determine the role of domestic dogs in transmission of visceral leishmaniasis in eastern Sudan. A cross-sectional survey was conducted in 10 villages along the River Rahad in eastern Sudan to elucidate the role of domestic dogs (Canis familiaris, Linnaeus, 1758) as a reservoir host of Leishmania donovani. In this study, 87 dogs were screened for infection by Leishmania donovani. Blood and lymph node samples were taken from 87 and 33 dogs respectively and subsequently screened by the Polymerase Chain Reaction (PCR) and Direct Agglutination Test (DAT) test. Additional lymph node smears were processed for microscopy and parasite culture. Host preference of the visceral leishmaniasis (VL) vector in the area, Phlebotomus orientalis, and other sandflies for the Nile rat (Arvicanthis niloticus, É. Geoffrey, 1803), the genet (Genetta genetta, Linnaeus, 1758), the mongoose (Herpeistes ichneumon, Linnaeus, 1758), and the domestic dog were determined by counting numbers of sand flies attracted to CDC traps that were baited by these animals. Results DAT on blood samples detected anti-Leishmania antibodies in 6 samples (6.9%). Two out of 87 (2.3%) blood samples tested were PCR positive, giving an amplification product of 560 bp. The two positive samples by PCR were also positive by DAT. However, none of the 33 lymph nodes aspirates were Leishmania positive when screened by microscopy, culture and genus-specific PCR. The dog-baited trap significantly attracted the highest number of P. orientalis and sand fly species (P < 0.001). This was followed by the Egyptian mongoose baited trap and less frequently by the genet baited trap. Conclusion It is concluded that the results obtained from host attraction studies indicate that dog is more attractive for P. orientalis than Egyptian mongoose, common genet and Nile rat. PMID:19534802

  19. Virus genomes and virus-host interactions in aquaculture animals.

    PubMed

    Zhang, QiYa; Gui, Jian-Fang

    2015-02-01

    Over the last 30 years, aquaculture has become the fastest growing form of agriculture production in the world, but its development has been hampered by a diverse range of pathogenic viruses. During the last decade, a large number of viruses from aquatic animals have been identified, and more than 100 viral genomes have been sequenced and genetically characterized. These advances are leading to better understanding about antiviral mechanisms and the types of interaction occurring between aquatic viruses and their hosts. Here, based on our research experience of more than 20 years, we review the wealth of genetic and genomic information from studies on a diverse range of aquatic viruses, including iridoviruses, herpesviruses, reoviruses, and rhabdoviruses, and outline some major advances in our understanding of virus-host interactions in animals used in aquaculture.

  20. Exploring the Spatio-Temporal Dynamics of Reservoir Hosts, Vectors, and Human Hosts of West Nile Virus: A Review of the Recent Literature

    PubMed Central

    Ozdenerol, Esra; Taff, Gregory N.; Akkus, Cem

    2013-01-01

    Over the last two decades West Nile Virus (WNV) has been responsible for significant disease outbreaks in humans and animals in many parts of the World. Its extremely rapid global diffusion argues for a better understanding of its geographic extent. The purpose of this inquiry was to explore spatio-temporal patterns of WNV using geospatial technologies to study populations of the reservoir hosts, vectors, and human hosts, in addition to the spatio-temporal interactions among these populations. Review of the recent literature on spatial WNV disease risk modeling led to the conclusion that numerous environmental factors might be critical for its dissemination. New Geographic Information Systems (GIS)-based studies are monitoring occurrence at the macro-level, and helping pinpoint areas of occurrence at the micro-level, where geographically-targeted, species-specific control measures are sometimes taken and more sophisticated methods of surveillance have been used. PMID:24284356

  1. The lyme disease pathogen has no effect on the survival of its rodent reservoir host.

    PubMed

    Voordouw, Maarten J; Lachish, Shelly; Dolan, Marc C

    2015-01-01

    Zoonotic pathogens that cause devastating morbidity and mortality in humans may be relatively harmless in their natural reservoir hosts. The tick-borne bacterium Borrelia burgdorferi causes Lyme disease in humans but few studies have investigated whether this pathogen reduces the fitness of its reservoir hosts under natural conditions. We analyzed four years of capture-mark-recapture (CMR) data on a population of white-footed mice, Peromyscus leucopus, to test whether B. burgdorferi and its tick vector affect the survival of this important reservoir host. We used a multi-state CMR approach to model mouse survival and mouse infection rates as a function of a variety of ecologically relevant explanatory factors. We found no effect of B. burgdorferi infection or tick burden on the survival of P. leucopus. Our estimates of the probability of infection varied by an order of magnitude (0.051 to 0.535) and were consistent with our understanding of Lyme disease in the Northeastern United States. B. burgdorferi establishes a chronic avirulent infection in their rodent reservoir hosts because this pathogen depends on rodent mobility to achieve transmission to its sedentary tick vector. The estimates of B. burgdorferi infection risk will facilitate future theoretical studies on the epidemiology of Lyme disease.

  2. Host entry by gamma-herpesviruses--lessons from animal viruses?

    PubMed

    Gillet, Laurent; Frederico, Bruno; Stevenson, Philip G

    2015-12-01

    The oncogenicity of gamma-herpesviruses (γHVs) motivates efforts to control them and their persistence makes early events key targets for intervention. Human γHVs are often assumed to enter naive hosts orally and infect B cells directly. However, neither assumption is supported by direct evidence, and vaccination with the Epstein-Barr virus (EBV) gp350, to block virion binding to B cells, failed to reduce infection rates. Thus, there is a need to re-evaluate assumptions about γHV host entry. Given the difficulty of analysing early human infections, potentially much can be learned from animal models. Genomic comparisons argue that γHVs colonized mammals long before humans speciation, and so that human γHVs are unlikely to differ dramatically in behaviour from those of other mammals. Murid Herpesvirus-4 (MuHV-4), which like EBV and the Kaposi's Sarcoma-associated Herpesvirus (KSHV) persists in memory B cells, enters new hosts via olfactory neurons and exploits myeloid cells to spread. Integrating these data with existing knowledge of human and veterinary γHVs suggests a new model of host entry, with potentially important implications for infection control.

  3. Novel methods for surveying reservoir hosts and vectors of Borrelia burgdorferi in Northern Minnesota

    NASA Astrophysics Data System (ADS)

    Seifert, Veronica Aili

    Lyme disease is the most prevalent tick-borne disease in North America and presents challenges to clinicians, researchers and the public in diagnosis, treatment and prevention. Lyme disease is caused by the spirochete, Borrelia burgdorferi, which is a zoonotic pathogen obligate upon hematophagous arthropod vectors and propagates in small mammal reservoir hosts. Identifying factors governing zoonotic diseases within regions of high-risk provides local health and agricultural agencies with necessary information to formulate public policy and implement treatment protocols to abate the rise and expansion of infectious disease outbreaks. In the United States, the documented primary reservoir host of Lyme disease is the white-footed mouse, Peromyscus leucopus, and the arthropod vector is the deer tick, Ixodes scapularis. Reducing the impact of Lyme disease will need novel methods for identifying both the reservoir host and the tick vector. The reservoir host, Peromyscus leucopus is difficult to distinguish from the virtually identical Peromyscus maniculatus that also is present in Northern Minnesota, a region where Lyme disease is endemic. Collection of the Ixodes tick, the Lyme disease vector, is difficult as this is season dependent and differs from year to year. This study develops new strategies to assess the extent of Borrelia burgdorferi in the local environment of Northern Minnesota. A selective and precise method to identify Peromyscus species was developed. This assay provides a reliable and definitive method to identify the reservoir host, Peromyscus leucopus from a physically identical and sympatric Peromyscus species, Peromyscus maniculatus. A new strategy to collect ticks for measuring the disbursement of Borrelia was employed. Students from local high schools were recruited to collect ticks. This strategy increased the available manpower to cover greater terrain, provided students with valuable experience in research methodology, and highlighted the

  4. Cytokine and Chemokine Expression in Kidneys during Chronic Leptospirosis in Reservoir and Susceptible Animal Models

    PubMed Central

    Matsui, Mariko; Roche, Louise; Geroult, Sophie; Soupé-Gilbert, Marie-Estelle; Monchy, Didier; Huerre, Michel; Goarant, Cyrille

    2016-01-01

    Leptospirosis is caused by pathogenic spirochetes of the genus Leptospira. Humans can be infected after exposure to contaminated urine of reservoir animals, usually rodents, regarded as typical asymptomatic carriers of leptospires. In contrast, accidental hosts may present an acute form of leptospirosis with a range of clinical symptoms including the development of Acute Kidney Injury (AKI). Chronic Kidney Disease (CKD) is considered as a possible AKI-residual sequela but little is known about the renal pathophysiology consequent to leptospirosis infection. Herein, we studied the renal morphological alterations in relation with the regulation of inflammatory cytokines and chemokines, comparing two experimental models of chronic leptospirosis, the golden Syrian hamster that survived the infection, becoming carrier of virulent leptospires, and the OF1 mouse, a usual reservoir of the bacteria. Animals were monitored until 28 days after injection with a virulent L. borgpetersenii serogroup Ballum to assess chronic infection. Hamsters developed morphological alterations in the kidneys with tubulointerstitial nephritis and fibrosis. Grading of lesions revealed higher scores in hamsters compared to the slight alterations observed in the mouse kidneys, irrespective of the bacterial load. Interestingly, pro-fibrotic TGF-β was downregulated in mouse kidneys. Moreover, cytokines IL-1β and IL-10, and chemokines MIP-1α/CCL3 and IP-10/CXCL-10 were significantly upregulated in hamster kidneys compared to mice. These results suggest a possible maintenance of inflammatory processes in the hamster kidneys with the infiltration of inflammatory cells in response to bacterial carriage, resulting in alterations of renal tissues. In contrast, lower expression levels in mouse kidneys indicated a better regulation of the inflammatory response and possible resolution processes likely related to resistance mechanisms. PMID:27219334

  5. Laboratory Investigations of African Pouched Rats (Cricetomys gambianus) as a Potential Reservoir Host Species for Monkeypox Virus

    PubMed Central

    Hutson, Christina L.; Nakazawa, Yoshinori J.; Self, Joshua; Olson, Victoria A.; Regnery, Russell L.; Braden, Zachary; Weiss, Sonja; Malekani, Jean; Jackson, Eddie; Tate, Mallory; Karem, Kevin L.; Rocke, Tonie E.; Osorio, Jorge E.; Damon, Inger K.; Carroll, Darin S.

    2015-01-01

    Abstract Monkeypox is a zoonotic disease endemic to central and western Africa, where it is a major public health concern. Although Monkeypox virus (MPXV) and monkeypox disease in humans have been well characterized, little is known about its natural history, or its maintenance in animal populations of sylvatic reservoir(s). In 2003, several species of rodents imported from Ghana were involved in a monkeypox outbreak in the United States with individuals of three African rodent genera (Cricetomys, Graphiurus, Funisciurus) shown to be infected with MPXV. Here, we examine the course of MPXV infection in Cricetomys gambianus (pouched Gambian rats) and this rodent species’ competence as a host for the virus. We obtained ten Gambian rats from an introduced colony in Grassy Key, Florida and infected eight of these via scarification with a challenge dose of 4X104 plaque forming units (pfu) from either of the two primary clades of MPXV: Congo Basin (C-MPXV: n = 4) or West African (W-MPXV: n = 4); an additional 2 animals served as PBS controls. Viral shedding and the effect of infection on activity and physiological aspects of the animals were measured. MPXV challenged animals had significantly higher core body temperatures, reduced activity and increased weight loss than PBS controls. Viable virus was found in samples taken from animals in both experimental groups (C-MPXV and W-MPXV) between 3 and 27 days post infection (p.i.) (up to 1X108 pfu/ml), with viral DNA found until day 56 p.i. The results from this work show that Cricetomys gambianus (and by inference, probably the closely related species, Cricetomys emini) can be infected with MPXV and shed viable virus particles; thus suggesting that these animals may be involved in the maintenance of MPXV in wildlife mammalian populations. More research is needed to elucidate the epidemiology of MPXV and the role of Gambian rats and other species. PMID:26517724

  6. Laboratory Investigations of African Pouched Rats (Cricetomys gambianus) as a Potential Reservoir Host Species for Monkeypox Virus.

    PubMed

    Hutson, Christina L; Nakazawa, Yoshinori J; Self, Joshua; Olson, Victoria A; Regnery, Russell L; Braden, Zachary; Weiss, Sonja; Malekani, Jean; Jackson, Eddie; Tate, Mallory; Karem, Kevin L; Rocke, Tonie E; Osorio, Jorge E; Damon, Inger K; Carroll, Darin S

    2015-01-01

    Monkeypox is a zoonotic disease endemic to central and western Africa, where it is a major public health concern. Although Monkeypox virus (MPXV) and monkeypox disease in humans have been well characterized, little is known about its natural history, or its maintenance in animal populations of sylvatic reservoir(s). In 2003, several species of rodents imported from Ghana were involved in a monkeypox outbreak in the United States with individuals of three African rodent genera (Cricetomys, Graphiurus, Funisciurus) shown to be infected with MPXV. Here, we examine the course of MPXV infection in Cricetomys gambianus (pouched Gambian rats) and this rodent species' competence as a host for the virus. We obtained ten Gambian rats from an introduced colony in Grassy Key, Florida and infected eight of these via scarification with a challenge dose of 4X104 plaque forming units (pfu) from either of the two primary clades of MPXV: Congo Basin (C-MPXV: n = 4) or West African (W-MPXV: n = 4); an additional 2 animals served as PBS controls. Viral shedding and the effect of infection on activity and physiological aspects of the animals were measured. MPXV challenged animals had significantly higher core body temperatures, reduced activity and increased weight loss than PBS controls. Viable virus was found in samples taken from animals in both experimental groups (C-MPXV and W-MPXV) between 3 and 27 days post infection (p.i.) (up to 1X108 pfu/ml), with viral DNA found until day 56 p.i. The results from this work show that Cricetomys gambianus (and by inference, probably the closely related species, Cricetomys emini) can be infected with MPXV and shed viable virus particles; thus suggesting that these animals may be involved in the maintenance of MPXV in wildlife mammalian populations. More research is needed to elucidate the epidemiology of MPXV and the role of Gambian rats and other species.

  7. Effect of the Latent Reservoir on the Evolution of HIV at the Within- and Between-Host Levels

    PubMed Central

    Doekes, Hilje M.; Fraser, Christophe; Lythgoe, Katrina A.

    2017-01-01

    The existence of long-lived reservoirs of latently infected CD4+ T cells is the major barrier to curing HIV, and has been extensively studied in this light. However, the effect of these reservoirs on the evolutionary dynamics of the virus has received little attention. Here, we present a within-host quasispecies model that incorporates a long-lived reservoir, which we then nest into an epidemiological model of HIV dynamics. For biologically plausible parameter values, we find that the presence of a latent reservoir can severely delay evolutionary dynamics within a single host, with longer delays associated with larger relative reservoir sizes and/or homeostatic proliferation of cells within the reservoir. These delays can fundamentally change the dynamics of the virus at the epidemiological scale. In particular, the delay in within-host evolutionary dynamics can be sufficient for the virus to evolve intermediate viral loads consistent with maximising transmission, as is observed, and not the very high viral loads that previous models have predicted, an effect that can be further enhanced if viruses similar to those that initiate infection are preferentially transmitted. These results depend strongly on within-host characteristics such as the relative reservoir size, with the evolution of intermediate viral loads observed only when the within-host dynamics are sufficiently delayed. In conclusion, we argue that the latent reservoir has important, and hitherto under-appreciated, roles in both within- and between-host viral evolution. PMID:28103248

  8. Effect of the Latent Reservoir on the Evolution of HIV at the Within- and Between-Host Levels.

    PubMed

    Doekes, Hilje M; Fraser, Christophe; Lythgoe, Katrina A

    2017-01-01

    The existence of long-lived reservoirs of latently infected CD4+ T cells is the major barrier to curing HIV, and has been extensively studied in this light. However, the effect of these reservoirs on the evolutionary dynamics of the virus has received little attention. Here, we present a within-host quasispecies model that incorporates a long-lived reservoir, which we then nest into an epidemiological model of HIV dynamics. For biologically plausible parameter values, we find that the presence of a latent reservoir can severely delay evolutionary dynamics within a single host, with longer delays associated with larger relative reservoir sizes and/or homeostatic proliferation of cells within the reservoir. These delays can fundamentally change the dynamics of the virus at the epidemiological scale. In particular, the delay in within-host evolutionary dynamics can be sufficient for the virus to evolve intermediate viral loads consistent with maximising transmission, as is observed, and not the very high viral loads that previous models have predicted, an effect that can be further enhanced if viruses similar to those that initiate infection are preferentially transmitted. These results depend strongly on within-host characteristics such as the relative reservoir size, with the evolution of intermediate viral loads observed only when the within-host dynamics are sufficiently delayed. In conclusion, we argue that the latent reservoir has important, and hitherto under-appreciated, roles in both within- and between-host viral evolution.

  9. Ecological Niche Modeling of main reservoir hosts of zoonotic cutaneous leishmaniasis in Iran.

    PubMed

    Gholamrezaei, Mostafa; Mohebali, Mehdi; Hanafi-Bojd, Ahmad Ali; Sedaghat, Mohammad Mehdi; Shirzadi, Mohammad Reza

    2016-08-01

    Zoonotic cutaneous leishmaniasis (ZCL), caused by Leishmania major, is a common zoonotic vector-borne disease in Iran. Close contact with infected reservoir hosts increases the probability of transmission of Leishmania parasite infections to susceptible humans. Four gerbil species (Rodentia: Gerbillidae) serve as the main reservoir hosts for ZCL in different endemic foci of Iran. These species include Rhombomys opimus, Meriones libycus, Meriones hurrianae and Tatera indica; while notable infection has been reported in Nesokia indica as well. The purpose of this study is to model the distribution of these reservoirs to identify the risk areas of ZCL. A data bank was developed including all published data during the period of 1970-2015. Maximum entropy model was used to find the most appropriate ecological niches for each species. The areas under curve obtained were 0.961, 0.927, 0.922, 0.997 and 0.899, instead of 1, for training test in R. opimus, M. libycus, T. indica, M. hurrianae and N. indica, respectively. The environmental variable with the highest gain when used in isolation was slope for R. opimus and N. indica, annual mean temperature for M. libycus, and seasonal precipitation for T. indica and M. hurrianae. Summation of presence probabilities for three main species, i.e., R. opimus, M. libycus and T. indica revealed favorable ecological niches in wide areas of 16 provinces. This is the first study to predict the distribution of ZCL reservoir hosts in Iran. Climatology and topography variables had high contributions toward the prediction of potential distribution of the main reservoir species; therefore, as climate changes, the models should be updated periodically with novel data, and the results should be used in disease-monitoring programs.

  10. Investigating the Potential Role of North American Animals as Hosts for Zika Virus.

    PubMed

    Ragan, Izabela K; Blizzard, Emily L; Gordy, Paul; Bowen, Richard A

    2017-03-01

    The recent emergence of the mosquito-borne Zika virus (ZIKV) in the Americas has become a global public health concern. We describe a series of experimental infections designed to investigate whether animals within certain taxonomic groups in North America have the potential to serve as ZIKV amplifying or maintenance hosts. Species investigated included armadillos, cottontail rabbits, goats, mink, chickens, pigeons, ground hogs, deer mice, cattle, raccoons, ducks, Syrian Golden hamsters, garter snakes, leopard frogs, house sparrows, and pigs. Infectious virus was isolated from blood only in frogs and armadillos; however, the magnitude of viremia was low. In addition, neutralizing antibodies were detected after infection in goats, rabbits, ducks, frogs, and pigs. This study indicates that the animals tested to date are unlikely to act as animal reservoirs for ZIKV, but that rabbits and pigs could potentially serve as sentinel species. Understanding the transmission cycle and maintenance of ZIKV in animals will help in developing effective surveillance programs and preventative measures for future outbreaks.

  11. Borrelia burgdorferi Manipulates Innate and Adaptive Immunity to Establish Persistence in Rodent Reservoir Hosts

    PubMed Central

    Tracy, Karen E.; Baumgarth, Nicole

    2017-01-01

    Borrelia burgdorferi sensu lato species complex is capable of establishing persistent infections in a wide variety of species, particularly rodents. Infection is asymptomatic or mild in most reservoir host species, indicating successful co-evolution of the pathogen with its natural hosts. However, infected humans and other incidental hosts can develop Lyme disease, a serious inflammatory syndrome characterized by tissue inflammation of joints, heart, muscles, skin, and CNS. Although B. burgdorferi infection induces both innate and adaptive immune responses, they are ultimately ineffective in clearing the infection from reservoir hosts, leading to bacterial persistence. Here, we review some mechanisms by which B. burgdorferi evades the immune system of the rodent host, focusing in particular on the effects of innate immune mechanisms and recent findings suggesting that T-dependent B cell responses are subverted during infection. A better understanding of the mechanisms causing persistence in rodents may help to increase our understanding of the pathogenesis of Lyme disease and ultimately aid in the development of therapies that support effective clearance of the bacterial infection by the host’s immune system. PMID:28265270

  12. Environmental influences on virus-host interactions in an Australian subtropical reservoir.

    PubMed

    Säwström, Christin; Pollard, Peter

    2012-02-01

    Viral and prokaryotic interactions in freshwaters have been investigated worldwide but there are few temporal studies in the tropics and none in the sub-tropics. In this 10-month study, we examined temporal changes in virus-host interactions and viral life cycles (lytic versus lysogenic) in relation to the prevailing environmental conditions in a subtropical water reservoir (Wivenhoe) in southeast Queensland, Australia. Heterotrophic prokaryotes and picocyanobacteria were positively correlated with concentrations of viruses throughout the study, indicating the presence of both bacteriophages and cyanophages in the reservoir. The percentage of heterotrophic prokaryotes and picocyanobacteria containing intracellular viruses (FVIC) ranged between 0.2% and 2.4% and did not vary significantly over the 10-month study, whereas lysogenic heterotrophic prokaryotes were only detected in the drier months of June and July. Spearman rank correlation analysis showed that the oxidative-reduction potential (ORP) of the water reservoir influenced the concentrations of viruses, heterotrophic prokaryotes and picocyanobacteria significantly, with low ORP offering a favourable environment for these components. There was a negative relationship between FVIC and rainfall suggesting the associated run-off altered virus-host interactions. Overall, our study provides novel information and inferences on how virus-host interactions in subtropical freshwaters might respond to changes in precipitation predicted to occur with global climate change.

  13. Zoonotic Hepatitis E Virus: Classification, Animal Reservoirs and Transmission Routes.

    PubMed

    Doceul, Virginie; Bagdassarian, Eugénie; Demange, Antonin; Pavio, Nicole

    2016-10-03

    During the past ten years, several new hepatitis E viruses (HEVs) have been identified in various animal species. In parallel, the number of reports of autochthonous hepatitis E in Western countries has increased as well, raising the question of what role these possible animal reservoirs play in human infections. The aim of this review is to present the recent discoveries of animal HEVs and their classification within the Hepeviridae family, their zoonotic and species barrier crossing potential, and possible use as models to study hepatitis E pathogenesis. Lastly, this review describes the transmission pathways identified from animal sources.

  14. Immunology of Entamoeba histolytica in human and animal hosts.

    PubMed

    Trissl, D

    1982-01-01

    Although Entamoeba histolytica induces humoral and cellular immune responses in both human and animal hosts, there is no indication of postinfection immunity in humans; in contrast, several other mammals are protected by prior infection or immunization. The exacerbation of the disease by immunosuppression suggests a protective function of still-unknown defense mechanisms. Specific local and circulating antibodies are produced regularly during invasive amebiasis. Although serum antibodies, together with complement, are lytic to the trophozoites in vitro, the poor correlation of these antibodies with resistance contradicts a protective capacity in vivo. The parasite may evade harm by shedding antigen-antibody complexes from its surface. Demonstration of immediate-type skin reactions, elevated IgE titers, and specific antiamebic IgE suggests that anaphylaxis occurs. The function of the anaphylactic reaction in pathology and resistance remains to be studied. Delayed hypersensitivity parallels healing or resistance and is retarded in human hepatic amebiasis. This observation is consistent with a protective role of cell-mediated immunity.

  15. Infectiousness of Sylvatic and Synanthropic Small Rodents Implicates a Multi-host Reservoir of Leishmania (Viannia) braziliensis

    PubMed Central

    F. Brito, Maria E.; Carvalho, Francisco G.; Carvalho, Ana Waléria S.; Soares, Fábia; Carvalho, Silvia M.; Costa, Pietra L.; Zampieri, Ricardo; Floeter-Winter, Lucile M.; Shaw, Jeffrey J.; Brandão-Filho, Sinval P.

    2015-01-01

    Background The possibility that a multi-host wildlife reservoir is responsible for maintaining transmission of Leishmania (Viannia) braziliensis causing human cutaneous and mucocutaneous leishmaniasis is tested by comparative analysis of infection progression and infectiousness to sandflies in rodent host species previously shown to have high natural infection prevalences in both sylvatic or/and peridomestic habitats in close proximity to humans in northeast Brazil. Methods The clinical and parasitological outcomes, and infectiousness to sandflies, were observed in 54 colonized animals of three species (18 Necromys lasiurus, 18 Nectomys squamipes and 18 Rattus rattus) experimentally infected with high (5.5×106/ml) or low (2.8×105/ml) dose L. (V.) braziliensis (MBOL/BR/2000/CPqAM95) inoculum. Clinical signs of infection were monitored daily. Whole animal xenodiagnoses were performed 6 months post inoculation using Lutzomyia longipalpis originating from flies caught in Passira, Pernambuco, after this parasite evaluation was performed at necropsy. Heterogeneities in Leishmania parasite loads were measured by quantitative PCR in ear skin, liver and spleen tissues. Results All three rodent species proved to establish infection characterized by short-term self-resolving skin lesions, located on ears and tail but not on footpads (one site of inoculation), and variable parasite loads detected in all three tissues with maximum burdens of 8.1×103 (skin), 2.8×103 (spleen), and 8.9×102 (liver). All three host species, 18/18 N. lasiurus, 10/18 N. squamipes and 6/18 R. rattus, also proved infectious to sandflies in cross-sectional study. R. rattus supported significantly lower tissue parasite loads compared to those in N. lasiurus and N. squamipes, and N. lasiurus appeared to be more infectious, on average, than either N. squamipes or R. rattus. Conclusions A multi-host reservoir of cutaneous leishmaniasis is indicated in this region of Brazil, though with apparent

  16. Host species exploitation and discrimination by animal parasites.

    PubMed

    Forbes, Mark R; Morrill, André; Schellinck, Jennifer

    2017-05-05

    Parasite species often show differential fitness on different host species. We developed an equation-based model to explore conditions favouring host species exploitation and discrimination. In our model, diploid infective stages randomly encountered hosts of two species; the parasite's relative fitness in exploiting each host species, and its ability to discriminate between them, was determined by the parasite's genotype at two independent diallelic loci. Relative host species frequency determined allele frequencies at the exploitation locus, whereas differential fitness and combined host density determined frequency of discrimination alleles. The model predicts instances where populations contain mixes of discriminatory and non-discriminatory infective stages. Also, non-discriminatory parasites should evolve when differential fitness is low to moderate and when combined host densities are low, but not so low as to cause parasite extinction. A corollary is that parasite discrimination (and host-specificity) increases with higher combined host densities. Instances in nature where parasites fail to discriminate when differential fitness is extreme could be explained by one host species evolving resistance, following from earlier selection for parasite non-discrimination. Similar results overall were obtained for haploid extensions of the model. Our model emulates multi-host associations and has implications for understanding broadening of host species ranges by parasites.This article is part of the themed issue 'Opening the black box: re-examining the ecology and evolution of parasite transmission'.

  17. Host species exploitation and discrimination by animal parasites

    PubMed Central

    Forbes, Mark R.; Morrill, André; Schellinck, Jennifer

    2017-01-01

    Parasite species often show differential fitness on different host species. We developed an equation-based model to explore conditions favouring host species exploitation and discrimination. In our model, diploid infective stages randomly encountered hosts of two species; the parasite's relative fitness in exploiting each host species, and its ability to discriminate between them, was determined by the parasite's genotype at two independent diallelic loci. Relative host species frequency determined allele frequencies at the exploitation locus, whereas differential fitness and combined host density determined frequency of discrimination alleles. The model predicts instances where populations contain mixes of discriminatory and non-discriminatory infective stages. Also, non-discriminatory parasites should evolve when differential fitness is low to moderate and when combined host densities are low, but not so low as to cause parasite extinction. A corollary is that parasite discrimination (and host-specificity) increases with higher combined host densities. Instances in nature where parasites fail to discriminate when differential fitness is extreme could be explained by one host species evolving resistance, following from earlier selection for parasite non-discrimination. Similar results overall were obtained for haploid extensions of the model. Our model emulates multi-host associations and has implications for understanding broadening of host species ranges by parasites. This article is part of the themed issue ‘Opening the black box: re-examining the ecology and evolution of parasite transmission’. PMID:28289258

  18. Effects of Salinity and Sea Level Change on Permafrost-Hosted Methane Hydrate Reservoirs

    NASA Astrophysics Data System (ADS)

    Elwood-Madden, M.

    2010-12-01

    Recent observations of methane release from sediments on the circum-arctic continental shelf indicate that arctic warming is likely leading to increased fluxes of methane . Thermodynamics predicts that 2-4 degree increases in global temperature will lead to massive marine hydrate decomposition; however, the rate of warming deep ocean waters and sediments is fairly slow, resulting in modest fluxes of methane over hundreds to thousands of years. In contrast, increasing arctic temperatures and rising sea level may have immediate effects on permafrost-hosted hydrate deposits. Rising sea level affects both the geothermal gradient of the region and the salinity of pore waters, leading to hydrate destabilization (Figure 1). Seawater infiltration of permafrost may be currently dissociating permafrost-hosted methane hydrate through a combination of mechanisms: shifting geothermal gradients to higher temperatures, addition of salts due to seawater encroachment, and the transition from solid state diffusion of methane through overlying ice cemented permafrost to mass transfer through seawater-saturated sediments via aqueous diffusion, advection, or ebullition. Effects of seawater erosion of permafrost have been observed in arctic coastal areas, and degradation of arctic permafrost is predicted to continue, especially in coastal areas. However, the rate at which these processes proceed and their effects on permafrost-hosted methane hydrates have been largely uninvestigated. Changes in geothermal gradient alone take hundreds to thousands of years to affect relatively deep hydrate reservoirs. However, warmer temperatures combined with freezing point depression effects of seawater may lead to rapid melting of permafrost ice, thus accelerating the transfer of heat to the hydrate reservoirs and changing the mass transfer mechanism of methane release from slow solid state diffusion through ice to more rapid aqueous diffusion, advection, or ebullition. Therefore, we hypothesize that

  19. Laboratory investigations of African Pouched Rats (Cricetomys gambianus) as a potential reservoir host species for Monkeypox Virus

    USGS Publications Warehouse

    Hutson, Christina L.; Nakazawa, Yoshinori J.; Self, Joshua; Olson, Victoria A.; Regnery, Russell L.; Braden, Zachary; Weiss, Sonja; Malekani, Jean; Jackson, Eddie; Tate, Mallory; Karem, Kevin L.; Rocke, Tonie E.; Osorio, Jorge E.; Damon, Inger K.; Carroll, Darin S.

    2015-01-01

    Monkeypox is a zoonotic disease endemic to central and western Africa, where it is a major public health concern. Although Monkeypox virus (MPXV) and monkeypox disease in humans have been well characterized, little is known about its natural history, or its maintenance in animal populations of sylvatic reservoir(s). In 2003, several species of rodents imported from Ghana were involved in a monkeypox outbreak in the United States with individuals of three African rodent genera (Cricetomys, Graphiurus, Funisciurus) shown to be infected with MPXV. Here, we examine the course of MPXV infection in Cricetomys gambianus (pouched Gambian rats) and this rodent species’ competence as a host for the virus. We obtained ten Gambian rats from an introduced colony in Grassy Key, Florida and infected eight of these via scarification with a challenge dose of 4X104 plaque forming units (pfu) from either of the two primary clades of MPXV: Congo Basin (C-MPXV: n = 4) or West African (W-MPXV: n = 4); an additional 2 animals served as PBS controls. Viral shedding and the effect of infection on activity and physiological aspects of the animals were measured. MPXV challenged animals had significantly higher core body temperatures, reduced activity and increased weight loss than PBS controls. Viable virus was found in samples taken from animals in both experimental groups (C-MPXV and W-MPXV) between 3 and 27 days post infection (p.i.) (up to 1X108pfu/ml), with viral DNA found until day 56 p.i. The results from this work show that Cricetomys gambianus (and by inference, probably the closely related species, Cricetomys emini) can be infected with MPXV and shed viable virus particles; thus suggesting that these animals may be involved in the maintenance of MPXV in wildlife mammalian populations. More research is needed to elucidate the epidemiology of MPXV and the role of Gambian rats and other species.

  20. Wildlife reservoirs of bovine tuberculosis worldwide: hosts, pathology, surveillance, and control.

    PubMed

    Fitzgerald, S D; Kaneene, J B

    2013-05-01

    Bovine tuberculosis due to Mycobacterium bovis is a zoonotic disease classically carried by cattle and spilling over into humans primarily by the ingestion of milk. However, in recent decades, there have been many endemic geographic localities where M. bovis has been detected infecting wildlife reservoirs, limiting the progress toward eradication of this disease from cattle. These include cervids in North America, badgers in Great Britain, feral pigs in Europe, brushtailed possums in New Zealand, and buffalo in South Africa. An overview of these wildlife hosts will provide insight into how these reservoirs maintain and spread the disease. In addition, the authors summarize the pathology, current ongoing methods for surveillance, and control. In many instances, it has proven to be more difficult to control or eradicate bovine tuberculosis in wild free-ranging species than in domesticated cattle. Furthermore, human influences have often contributed to the introduction and/or maintenance of the disease in wildlife species. Finally, some emerging themes regarding bovine tuberculosis establishment in wildlife hosts, as well as conclusions regarding management practices to assist in bovine tuberculosis control and eradication in wildlife, are offered.

  1. Internal structure of fault zones in geothermal reservoirs: Examples from palaeogeothermal fields and potential host rocks

    NASA Astrophysics Data System (ADS)

    Leonie Philipp, Sonja; Reyer, Dorothea; Meier, Silke; Bauer, Johanna F.; Afşar, Filiz

    2014-05-01

    Fault zones commonly have great effects on fluid transport in geothermal reservoirs. During fault slip all the pores and small fractures that meet with the slip plane become interconnected so that the inner part of the fault, the fault core, consisting of breccia or gouge, may suddenly develop a very high permeability. This is evidenced, for example by networks of mineral veins in deeply eroded fault zones in palaeogeothermal fields. Inactive faults, however, may have low permeabilities and even act as flow barriers. In natural and man-made geothermal reservoirs, the orientation of fault zones in relation to the current stress field and their internal structure needs be known as accurately as possible. One reason is that the activity of the fault zone depends on its angle to the principal stress directions. Another reason is that the outer part of a fault zone, the damage zone, comprises numerous fractures of various sizes. Here we present field examples of faults, and associated joints and mineral veins, in palaeogeothermal fields, and potential host rocks for man-made geothermal reservoirs, respectively. We studied several localities of different stratigraphies, lithologies and tectonic settings: (1) 58 fault zones in 22 outcrops from Upper Carboniferous to Upper Cretaceous in the Northwest German Basin (siliciclastic, carbonate and volcanic rocks); (2) 16 fault zones in 9 outcrops in Lower Permian to Middle Triassic (mainly sandstone, limestone and granite) in the Upper Rhine Graben; and (3) 74 fault zones in two coastal sections of Upper Triassic and Lower Jurassic age (mudstones and limestone-marl alternations) in the Bristol Channel Basin, UK. (1) and (2) are outcrop analogues of geothermal reservoir horizons, (3) represent palaeogeothermal fields with mineral veins. The field studies in the Northwest German Basin (1) show pronounced differences between normal-fault zones in carbonate and clastic rocks. In carbonate rocks clear damage zones occur that are

  2. Ehrlichia chaffeensis infection in the reservoir host (white-tailed deer) and in an incidental host (dog) is impacted by its prior growth in macrophage and tick cell environments.

    PubMed

    Nair, Arathy D S; Cheng, Chuanmin; Jaworski, Deborah C; Willard, Lloyd H; Sanderson, Michael W; Ganta, Roman R

    2014-01-01

    Ehrlichia chaffeensis, transmitted from Amblyomma americanum ticks, causes human monocytic ehrlichiosis. It also infects white-tailed deer, dogs and several other vertebrates. Deer are its reservoir hosts, while humans and dogs are incidental hosts. E. chaffeensis protein expression is influenced by its growth in macrophages and tick cells. We report here infection progression in deer or dogs infected intravenously with macrophage- or tick cell-grown E. chaffeensis or by tick transmission in deer. Deer and dogs developed mild fever and persistent rickettsemia; the infection was detected more frequently in the blood of infected animals with macrophage inoculum compared to tick cell inoculum or tick transmission. Tick cell inoculum and tick transmission caused a drop in tick infection acquisition rates compared to infection rates in ticks fed on deer receiving macrophage inoculum. Independent of deer or dogs, IgG antibody response was higher in animals receiving macrophage inoculum against macrophage-derived Ehrlichia antigens, while it was significantly lower in the same animals against tick cell-derived Ehrlichia antigens. Deer infected with tick cell inoculum and tick transmission caused a higher antibody response to tick cell cultured bacterial antigens compared to the antibody response for macrophage cultured antigens for the same animals. The data demonstrate that the host cell-specific E. chaffeensis protein expression influences rickettsemia in a host and its acquisition by ticks. The data also reveal that tick cell-derived inoculum is similar to tick transmission with reduced rickettsemia, IgG response and tick acquisition of E. chaffeensis.

  3. Tacaribe Virus Causes Fatal Infection of An Ostensible Reservoir Host, the Jamaican Fruit Bat

    PubMed Central

    Cogswell-Hawkinson, Ann; Bowen, Richard; James, Stephanie; Gardiner, David; Calisher, Charles H.; Adams, Rick

    2012-01-01

    Tacaribe virus (TCRV) was first isolated from 11 Artibeus species bats captured in Trinidad in the 1950s during a rabies virus surveillance program. Despite significant effort, no evidence of infection of other mammals, mostly rodents, was found, suggesting that no other vertebrates harbored TCRV. For this reason, it was hypothesized that TCRV was naturally hosted by artibeus bats. This is in stark contrast to other arenaviruses with known hosts, all of which are rodents. To examine this hypothesis, we conducted experimental infections of Jamaican fruit bats (Artibeus jamaicensis) to determine whether they could be persistently infected without substantial pathology. We subcutaneously or intranasally infected bats with TCRV strain TRVL-11573, the only remaining strain of TCRV, and found that low-dose (104 50% tissue culture infective dose [TCID50]) inoculations resulted in asymptomatic and apathogenic infection and virus clearance, while high-dose (106 TCID50) inoculations caused substantial morbidity and mortality as early as 10 days postinfection. Uninoculated cage mates failed to seroconvert, and viral RNA was not detected in their tissues, suggesting that transmission did not occur. Together, these data suggest that A. jamaicensis bats may not be a reservoir host for TCRV. PMID:22379103

  4. Tacaribe virus causes fatal infection of an ostensible reservoir host, the Jamaican fruit bat.

    PubMed

    Cogswell-Hawkinson, Ann; Bowen, Richard; James, Stephanie; Gardiner, David; Calisher, Charles H; Adams, Rick; Schountz, Tony

    2012-05-01

    Tacaribe virus (TCRV) was first isolated from 11 Artibeus species bats captured in Trinidad in the 1950s during a rabies virus surveillance program. Despite significant effort, no evidence of infection of other mammals, mostly rodents, was found, suggesting that no other vertebrates harbored TCRV. For this reason, it was hypothesized that TCRV was naturally hosted by artibeus bats. This is in stark contrast to other arenaviruses with known hosts, all of which are rodents. To examine this hypothesis, we conducted experimental infections of Jamaican fruit bats (Artibeus jamaicensis) to determine whether they could be persistently infected without substantial pathology. We subcutaneously or intranasally infected bats with TCRV strain TRVL-11573, the only remaining strain of TCRV, and found that low-dose (10(4) 50% tissue culture infective dose [TCID(50)]) inoculations resulted in asymptomatic and apathogenic infection and virus clearance, while high-dose (10(6) TCID(50)) inoculations caused substantial morbidity and mortality as early as 10 days postinfection. Uninoculated cage mates failed to seroconvert, and viral RNA was not detected in their tissues, suggesting that transmission did not occur. Together, these data suggest that A. jamaicensis bats may not be a reservoir host for TCRV.

  5. Novel Bacteroides host strains for detection of human- and animal-specific bacteriophages in water.

    PubMed

    Wicki, Melanie; Auckenthaler, Adrian; Felleisen, Richard; Tanner, Marcel; Baumgartner, Andreas

    2011-03-01

    Bacteriophages active against specific Bacteroides host strains were shown to be suitable for detection of human faecal pollution. However, the practical application of this finding is limited because some specific host strains were restricted to certain geographic regions. In this study, novel Bacteroides host strains were isolated that discriminate human and animal faecal pollution in Switzerland. Two strains specific for bacteriophages present in human faecal contamination and three strains specific for bacteriophages indicating animal faecal contamination were evaluated. Bacteriophages infecting human strains were exclusively found in human wastewater, whereas animal strains detected bacteriophages only in animal waste. The newly isolated host strains could be used to determine the source of surface and spring water faecal contamination in field situations. Applying the newly isolated host Bacteroides thetaiotaomicron ARABA 84 for detection of bacteriophages allowed the detection of human faecal contamination in spring water.

  6. Experimental Infection of Potential Reservoir Hosts with Venezuelan Equine Encephalitis Virus, Mexico

    PubMed Central

    Deardorff, Eleanor R.; Forrester, Naomi L.; Travassos da Rosa, Amelia P.; Estrada-Franco, Jose G.; Navarro-Lopez, Roberto; Tesh, Robert B.

    2009-01-01

    In 1993, an outbreak of encephalitis among 125 affected equids in coastal Chiapas, Mexico, resulted in a 50% case-fatality rate. The outbreak was attributed to Venezuelan equine encephalitis virus (VEEV) subtype IE, not previously associated with equine disease and death. To better understand the ecology of this VEEV strain in Chiapas, we experimentally infected 5 species of wild rodents and evaluated their competence as reservoir and amplifying hosts. Rodents from 1 species (Baiomys musculus) showed signs of disease and died by day 8 postinoculation. Rodents from the 4 other species (Liomys salvini, Oligoryzomys fulvescens, Oryzomys couesi, and Sigmodon hispidus) became viremic but survived and developed neutralizing antibodies, indicating that multiple species may contribute to VEEV maintenance. By infecting numerous rodent species and producing adequate viremia, VEEV may increase its chances of long-term persistence in nature and could increase risk for establishment in disease-endemic areas and amplification outside the disease-endemic range. PMID:19331726

  7. Red fox (Vulpes vulpes) as a potential reservoir host of cardiorespiratory parasites in Bosnia and Herzegovina.

    PubMed

    Hodžić, Adnan; Alić, Amer; Klebić, Ismar; Kadrić, Mirsad; Brianti, Emanuele; Duscher, Georg Gerhard

    2016-06-15

    Red fox (Vulpes vulpes) is considered as reservoir of different cardiorespiratory parasites of veterinary and medical importance. Since data on cardiorespiratory parasites in foxes in Bosnia and Herzegovina are still lacking, the aims of the present study were to (i) investigate the prevalence and geographical distribution of these parasites, (ii) determine genetic diversity of detected parasite species, and (iii) to estimate the role of foxes in the transmission cycle to companion animals and humans. Four species, morphologically and molecularly identified as Eucoleus boehmi (64.6%; 51/79), Eucoleus aerophilus (69.7%; 154/221), Crenosoma vulpis (45.7%; 101/221) and Linguatula serrata (1.3%; 1/79) were retrieved from nasal cavity and lungs in 184 (83.3%) animals. The occurrence of heartworms, Angiostrongylus vasorum and Dirofilaria immitis was not detected by necropsy or PCR. Furthermore, three distinct haplotypes of E. aerophilus (I, III, XV) and two of C. vulpis (I, II) previously reported in pet animals and wild carnivores were confirmed in this study. A new haplotype of C. vulpis (designated as haplotype V) was also identified based on 12S rRNA gene for the first time. The present study indicates a high prevalence and wide distribution of nasal and lung nematodes in fox population in Bosnia and Herzegovina, and supports the existence of transmission patterns between wildlife and pet animals.

  8. Plasmodium knowlesi: Reservoir Hosts and Tracking the Emergence in Humans and Macaques

    PubMed Central

    Lee, Kim-Sung; Divis, Paul C. S.; Zakaria, Siti Khatijah; Matusop, Asmad; Julin, Roynston A.; Conway, David J.; Cox-Singh, Janet; Singh, Balbir

    2011-01-01

    Plasmodium knowlesi, a malaria parasite originally thought to be restricted to macaques in Southeast Asia, has recently been recognized as a significant cause of human malaria. Unlike the benign and morphologically similar P. malariae, these parasites can lead to fatal infections. Malaria parasites, including P. knowlesi, have not yet been detected in macaques of the Kapit Division of Malaysian Borneo, where the majority of human knowlesi malaria cases have been reported. In order to extend our understanding of the epidemiology and evolutionary history of P. knowlesi, we examined 108 wild macaques for malaria parasites and sequenced the circumsporozoite protein (csp) gene and mitochondrial (mt) DNA of P. knowlesi isolates derived from macaques and humans. We detected five species of Plasmodium (P. knowlesi, P. inui, P. cynomolgi, P. fieldi and P. coatneyi) in the long-tailed and pig-tailed macaques, and an extremely high prevalence of P. inui and P. knowlesi. Macaques had a higher number of P. knowlesi genotypes per infection than humans, and some diverse alleles of the P. knowlesi csp gene and certain mtDNA haplotypes were shared between both hosts. Analyses of DNA sequence data indicate that there are no mtDNA lineages associated exclusively with either host. Furthermore, our analyses of the mtDNA data reveal that P. knowlesi is derived from an ancestral parasite population that existed prior to human settlement in Southeast Asia, and underwent significant population expansion approximately 30,000–40,000 years ago. Our results indicate that human infections with P. knowlesi are not newly emergent in Southeast Asia and that knowlesi malaria is primarily a zoonosis with wild macaques as the reservoir hosts. However, ongoing ecological changes resulting from deforestation, with an associated increase in the human population, could enable this pathogenic species of Plasmodium to switch to humans as the preferred host. PMID:21490952

  9. Host behaviour–parasite feedback: an essential link between animal behaviour and disease ecology

    PubMed Central

    Archie, Elizabeth A.; Craft, Meggan E.; Hawley, Dana M.; Martin, Lynn B.; Moore, Janice; White, Lauren

    2016-01-01

    Animal behaviour and the ecology and evolution of parasites are inextricably linked. For this reason, animal behaviourists and disease ecologists have been interested in the intersection of their respective fields for decades. Despite this interest, most research at the behaviour–disease interface focuses either on how host behaviour affects parasites or how parasites affect behaviour, with little overlap between the two. Yet, the majority of interactions between hosts and parasites are probably reciprocal, such that host behaviour feeds back on parasites and vice versa. Explicitly considering these feedbacks is essential for understanding the complex connections between animal behaviour and parasite ecology and evolution. To illustrate this point, we discuss how host behaviour–parasite feedbacks might operate and explore the consequences of feedback for studies of animal behaviour and parasites. For example, ignoring the feedback of host social structure on parasite dynamics can limit the accuracy of predictions about parasite spread. Likewise, considering feedback in studies of parasites and animal personalities may provide unique insight about the maintenance of variation in personality types. Finally, applying the feedback concept to links between host behaviour and beneficial, rather than pathogenic, microbes may shed new light on transitions between mutualism and parasitism. More generally, accounting for host behaviour–parasite feedbacks can help identify critical gaps in our understanding of how key host behaviours and parasite traits evolve and are maintained. PMID:27053751

  10. Host behaviour-parasite feedback: an essential link between animal behaviour and disease ecology.

    PubMed

    Ezenwa, Vanessa O; Archie, Elizabeth A; Craft, Meggan E; Hawley, Dana M; Martin, Lynn B; Moore, Janice; White, Lauren

    2016-04-13

    Animal behaviour and the ecology and evolution of parasites are inextricably linked. For this reason, animal behaviourists and disease ecologists have been interested in the intersection of their respective fields for decades. Despite this interest, most research at the behaviour-disease interface focuses either on how host behaviour affects parasites or how parasites affect behaviour, with little overlap between the two. Yet, the majority of interactions between hosts and parasites are probably reciprocal, such that host behaviour feeds back on parasites and vice versa. Explicitly considering these feedbacks is essential for understanding the complex connections between animal behaviour and parasite ecology and evolution. To illustrate this point, we discuss how host behaviour-parasite feedbacks might operate and explore the consequences of feedback for studies of animal behaviour and parasites. For example, ignoring the feedback of host social structure on parasite dynamics can limit the accuracy of predictions about parasite spread. Likewise, considering feedback in studies of parasites and animal personalities may provide unique insight about the maintenance of variation in personality types. Finally, applying the feedback concept to links between host behaviour and beneficial, rather than pathogenic, microbes may shed new light on transitions between mutualism and parasitism. More generally, accounting for host behaviour-parasite feedbacks can help identify critical gaps in our understanding of how key host behaviours and parasite traits evolve and are maintained.

  11. Undomesticated animals as a reservoir of multidrug-resistant Enterococcus in eastern Poland.

    PubMed

    Nowakiewicz, Aneta; Ziółkowska, Grażyna; Zięba, Przemysław; Kostruba, Anna

    2014-07-01

    To assess implications for public health we compared the resistance of Enterococcus spp. strains to antibacterial drugs in wild and exotic animals with strains originating in domesticated animals and characterized correlations between Enterococcus species, the source of the isolate, and the degree of resistance to selected antibiotics. All strains, regardless of source, were susceptible to β-lactams, gentamicin, linezolid, and teicoplanin; the highest resistance was to kanamycin, quinupristin, and rifampicin. Thirteen strains from undomesticated animals were resistant to vancomycin, and one strain, from a fox, was resistant to streptomycin (high-dose). Multidrug-resistant strains accounted for 46% of the strains from wild animals and 59% of the strains from an exotic animal (the Russian tortoise; Testudo horsfieldii). Despite the relatively low level of resistance in the strains isolated from wild and exotic animals, the large number of intermediately susceptible strains in these groups is an indication of the evolutionary character of the development of resistance, suggesting that these animals may be potential reservoirs of Enterococcus strains resistant to a wide panel of currently used antibiotics.

  12. Surveillance of hantaviruses in Poland: a study of animal reservoirs and human hantavirus disease in Subcarpathia.

    PubMed

    Michalski, Aleksander; Niemcewicz, Marcin; Bielawska-Drózd, Agata; Nowakowska, Anna; Gaweł, Jerzy; Pitucha, Grzegorz; Joniec, Justyna; Zielonka, Katarzyna; Marciniak-Niemcewicz, Anna; Kocik, Janusz

    2014-07-01

    The first cluster of hemorrhagic fever with renal syndrome (HFRS) in Poland was identified in 2007 in the Subcarpathian region. The natural environment of this area is a key habitat for hantavirus vectors. The animal reservoir of existing human HFRS clusters was studied to assess the occurrence of viruses (including Tula virus, Puumala virus, and Dobrava-Belgrade virus) among rodents. We examined 70 suspected human cases with symptoms corresponding to the clinical picture of HFRS. Serological analysis (indirect immunofluorescence assay and immunoblot) confirmed the presence of anti-hantavirus antibodies in 18 patients, which were surveyed with regard to developed symptoms and presumed rodent contact. Seroepidemiological analysis of newly confirmed human cases was performed, putative areas of human exposure were studied, and 194 rodents were subsequently captured from identified areas. Internal organs (lungs, heart, spleen, bladder, and kidneys) were collected from 64 Apodemus flavicollis, 55 Apodemus agrarius, 40 Myodes glareolus, 21 Mus musculus, and 14 Microtus arvalis and tested for the presence of hantavirus RNA by reverse transcription and subsequent real-time PCR. Positive samples were also tested by indirect immunofluorescence. Animal reservoir surveillance enabled the first detection of Puumala virus and Dobrava-Belgrade virus among animals in Poland. Furthermore, some places where rodents were captured correlated with areas of residence of laboratory-confirmed human cases and likely detected virus species. Moreover, three species of hantaviruses coexisting in a relatively small area were identified.

  13. Investigation of reservoir animals of Leptospira in the northern part of Miyazaki Prefecture.

    PubMed

    Koizumi, Nobuo; Muto, Maki; Yamamoto, Seigo; Baba, Yoshitaka; Kudo, Momotoshi; Tamae, Yoshinobu; Shimomura, Koji; Takatori, Ichiro; Iwakiri, Akira; Ishikawa, Koji; Soma, Hirotoshi; Watanabe, Haruo

    2008-11-01

    We surveyed reservoir animals of leptospires in the northern part of Miyazaki Prefecture, where a cluster of human leptospirosis had occurred during the summer of 2006. Leptospira was isolated from 6 of 57 large Japanese field mice (Apodemus speciosus). The serogroups of the isolates were Autumnalis (5 strains) and Hebdomadis (1 strain) and the partial nucleotide sequences of their flaB genes suggested that the isolates belonged to L. interrogans. The human patient sera reacted specifically with the Leptospira strain isolated from the mice captured around the area where each patient occurred, suggesting that mice are the source of human infection. We also detected leptospiral DNAs by flaB-polymerase chain reaction in the kidneys of large feral animals; wild boars (positive ratio 10.3%; 4 of 39) and deer (19.2%; 10 of 52). The Leptospira spp. harbored by these animals were deduced to be L. interrogans (in 5 animals) and L. borgpetersenii (in 9 animals) by the nucleotide sequences of the amplicons. Anti-Leptospira antibodies were also detected among symptomatic hound dogs. These results suggest that these feral animals may cause leptospirosis and pose a potential risk to hunters and workers in the meat processing industry.

  14. Utility of Filter Paper for Preserving Insects, Bacteria, and Host Reservoir DNA for Molecular Testing

    PubMed Central

    Karimian, F; Sedaghat, MM; Oshaghi, MA; Mohtarami, F; Dehkordi, A Sanei; Koosha, M; Akbari, S; Hashemi-Aghdam, SS

    2011-01-01

    Background: Appropriate methodology for storage biological materials, extraction of DNA, and proper DNA preservation is vital for studies involving genetic analysis of insects, bacteria, and reservoir hosts as well as for molecular diagnostics of pathogens carried by vectors and reservoirs. Here we tried to evaluate the utility of a simple filter paper-based for storage of insects, bacteria, rodent, and human DNAs using PCR assays. Methods: Total body or haemolymph of individual mosquitoes, sand flies or cockroaches squashed or placed on the paper respectively. Extracted DNA of five different bacteria species as well as blood specimens of human and great gerbil Rhombomys opimus was pipetted directly onto filter paper. The papers were stored in room temperature up to 12 months during 2009 until 2011. At monthly intervals, PCR was conducted using a 1-mm disk from the DNA impregnated filter paper as target DNA. PCR amplification was performed against different target genes of the organisms including the ITS2-rDNA of mosquitoes, mtDNA-COI of the sand flies and cockroaches, 16SrRNA gene of the bacteria, and the mtDNA-CytB of the vertebrates. Results: Successful PCR amplification was observed for all of the specimens regardless of the loci, taxon, or time of storage. The PCR amplification were ranged from 462 to 1500 bp and worked well for the specified target gene/s. Time of storage did not affect the amplification up to one year. Conclusion: The filter paper method is a simple and economical way to store, to preserve, and to distribute DNA samples for PCR analysis. PMID:22808417

  15. Human and animal isolates of Yersinia enterocolitica show significant serotype-specific colonization and host-specific immune defense properties.

    PubMed

    Schaake, Julia; Kronshage, Malte; Uliczka, Frank; Rohde, Manfred; Knuuti, Tobias; Strauch, Eckhard; Fruth, Angelika; Wos-Oxley, Melissa; Dersch, Petra

    2013-11-01

    Yersinia enterocolitica is a human pathogen that is ubiquitous in livestock, especially pigs. The bacteria are able to colonize the intestinal tract of a variety of mammalian hosts, but the severity of induced gut-associated diseases (yersiniosis) differs significantly between hosts. To gain more information about the individual virulence determinants that contribute to colonization and induction of immune responses in different hosts, we analyzed and compared the interactions of different human- and animal-derived isolates of serotypes O:3, O:5,27, O:8, and O:9 with murine, porcine, and human intestinal cells and macrophages. The examined strains exhibited significant serotype-specific cell binding and entry characteristics, but adhesion and uptake into different host cells were not host specific and were independent of the source of the isolate. In contrast, survival and replication within macrophages and the induced proinflammatory response differed between murine, porcine, and human macrophages, suggesting a host-specific immune response. In fact, similar levels of the proinflammatory cytokine macrophage inflammatory protein 2 (MIP-2) were secreted by murine bone marrow-derived macrophages with all tested isolates, but the equivalent interleukin-8 (IL-8) response of porcine bone marrow-derived macrophages was strongly serotype specific and considerably lower in O:3 than in O:8 strains. In addition, all tested Y. enterocolitica strains caused a considerably higher level of secretion of the anti-inflammatory cytokine IL-10 by porcine than by murine macrophages. This could contribute to limiting the severity of the infection (in particular of serotype O:3 strains) in pigs, which are the primary reservoir of Y. enterocolitica strains pathogenic to humans.

  16. Validation of qPCR Methods for the Detection of Mycobacterium in New World Animal Reservoirs.

    PubMed

    Housman, Genevieve; Malukiewicz, Joanna; Boere, Vanner; Grativol, Adriana D; Pereira, Luiz Cezar M; Silva, Ita de Oliveira; Ruiz-Miranda, Carlos R; Truman, Richard; Stone, Anne C

    2015-11-01

    Zoonotic pathogens that cause leprosy (Mycobacterium leprae) and tuberculosis (Mycobacterium tuberculosis complex, MTBC) continue to impact modern human populations. Therefore, methods able to survey mycobacterial infection in potential animal hosts are necessary for proper evaluation of human exposure threats. Here we tested for mycobacterial-specific single- and multi-copy loci using qPCR. In a trial study in which armadillos were artificially infected with M. leprae, these techniques were specific and sensitive to pathogen detection, while more traditional ELISAs were only specific. These assays were then employed in a case study to detect M. leprae as well as MTBC in wild marmosets. All marmosets were negative for M. leprae DNA, but 14 were positive for the mycobacterial rpoB gene assay. Targeted capture and sequencing of rpoB and other MTBC genes validated the presence of mycobacterial DNA in these samples and revealed that qPCR is useful for identifying mycobacterial-infected animal hosts.

  17. Distribution of Bartonella henselae variants in patients, reservoir hosts and vectors in Spain.

    PubMed

    Gil, Horacio; Escudero, Raquel; Pons, Inmaculada; Rodríguez-Vargas, Manuela; García-Esteban, Coral; Rodríguez-Moreno, Isabel; García-Amil, Cristina; Lobo, Bruno; Valcárcel, Félix; Pérez, Azucena; Jiménez, Santos; Jado, Isabel; Juste, Ramón; Segura, Ferrán; Anda, Pedro

    2013-01-01

    We have studied the diversity of B. henselae circulating in patients, reservoir hosts and vectors in Spain. In total, we have fully characterized 53 clinical samples from 46 patients, as well as 78 B. henselae isolates obtained from 35 cats from La Rioja and Catalonia (northeastern Spain), four positive cat blood samples from which no isolates were obtained, and three positive fleas by Multiple Locus Sequence Typing and Multiple Locus Variable Number Tandem Repeats Analysis. This study represents the largest series of human cases characterized with these methods, with 10 different sequence types and 41 MLVA profiles. Two of the sequence types and 35 of the profiles were not described previously. Most of the B. henselae variants belonged to ST5. Also, we have identified a common profile (72) which is well distributed in Spain and was found to persist over time. Indeed, this profile seems to be the origin from which most of the variants identified in this study have been generated. In addition, ST5, ST6 and ST9 were found associated with felines, whereas ST1, ST5 and ST8 were the most frequent sequence types found infecting humans. Interestingly, some of the feline associated variants never found on patients were located in a separate clade, which could represent a group of strains less pathogenic for humans.

  18. Distribution of Bartonella henselae Variants in Patients, Reservoir Hosts and Vectors in Spain

    PubMed Central

    Gil, Horacio; Escudero, Raquel; Pons, Inmaculada; Rodríguez-Vargas, Manuela; García-Esteban, Coral; Rodríguez-Moreno, Isabel; García-Amil, Cristina; Lobo, Bruno; Valcárcel, Félix; Pérez, Azucena; Jiménez, Santos; Jado, Isabel; Juste, Ramón; Segura, Ferrán; Anda, Pedro

    2013-01-01

    We have studied the diversity of B. henselae circulating in patients, reservoir hosts and vectors in Spain. In total, we have fully characterized 53 clinical samples from 46 patients, as well as 78 B. henselae isolates obtained from 35 cats from La Rioja and Catalonia (northeastern Spain), four positive cat blood samples from which no isolates were obtained, and three positive fleas by Multiple Locus Sequence Typing and Multiple Locus Variable Number Tandem Repeats Analysis. This study represents the largest series of human cases characterized with these methods, with 10 different sequence types and 41 MLVA profiles. Two of the sequence types and 35 of the profiles were not described previously. Most of the B. henselae variants belonged to ST5. Also, we have identified a common profile (72) which is well distributed in Spain and was found to persist over time. Indeed, this profile seems to be the origin from which most of the variants identified in this study have been generated. In addition, ST5, ST6 and ST9 were found associated with felines, whereas ST1, ST5 and ST8 were the most frequent sequence types found infecting humans. Interestingly, some of the feline associated variants never found on patients were located in a separate clade, which could represent a group of strains less pathogenic for humans. PMID:23874563

  19. Influenza virus reservoirs and intermediate hosts: dogs, horses, and new possibilities for influenza virus exposure of humans.

    PubMed

    Parrish, Colin R; Murcia, Pablo R; Holmes, Edward C

    2015-03-01

    Influenza A virus (IAV) infections in hosts outside the main aquatic bird reservoirs occur periodically. Although most such cross-species transmission events result in limited onward transmission in the new host, sustained influenza outbreaks have occurred in poultry and in a number of mammalian species, including humans, pigs, horses, seals, and mink. Recently, two distinct strains of IAV have emerged in domestic dogs, with each circulating widely for several years. Here, we briefly outline what is known about the role of intermediate hosts in influenza emergence, summarize our knowledge of the new canine influenza viruses (CIVs) and how they provide key new information on the process of host adaptation, and assess the risk these viruses pose to human populations.

  20. Bayou virus-associated hantavirus pulmonary syndrome in Eastern Texas: identification of the rice rat, Oryzomys palustris, as reservoir host.

    PubMed Central

    Torrez-Martinez, N.; Bharadwaj, M.; Goade, D.; Delury, J.; Moran, P.; Hicks, B.; Nix, B.; Davis, J. L.; Hjelle, B.

    1998-01-01

    We describe the third known case of hantavirus pulmonary syndrome (HPS) due to Bayou virus, from Jefferson County, Texas. By using molecular epidemiologic methods, we show that rice rats (Oryzomys palustris) are frequently infected with Bayou virus and that viral RNA sequences from HPS patients are similar to those from nearby rice rats. Bayou virus is associated with O. palustris; this rodent appears to be its predominant reservoir host. PMID:9452404

  1. Over-wintering tadpoles of Mixophyes fasciolatus act as reservoir host for Batrachochytrium dendrobatidis.

    PubMed

    Narayan, Edward J; Graham, Clara; McCallum, Hamish; Hero, Jean-Marc

    2014-01-01

    Batrachochytrium dendrobatidis (Bd), a cutaneous amphibian fungus that causes the lethal disease chytridiomycosis, has been implicated as a cause of many amphibian declines. Bd can tolerate low temperatures with an optimum thermal range from 17-24°C. It has been shown that Bd infection may result in species extinction, avoiding the transmission threshold presented by density dependent transmission theory. Prevalence of Bd during autumn and winter has been shown to be as low as 0% in some species. It is currently unclear how Bd persists in field conditions and what processes result in carry-over between seasons. It has been hypothesised that overwintering tadpoles may host Bd between breeding seasons. The Great Barred Frog (Mixophyes fasciolatus) is a common, stable and widespread species in Queensland, Australia, and is known to carry Bd. Investigation into Bd infection of different life stages of M. fasciolatus during seasonally low prevalence may potentially reveal persistence and carry-over methods between seasons. Metamorphs, juveniles, and adults were swabbed for Bd infection over three months (between March and May, 2011) at 5 sites of varying altitude (66 m-790 m). A total of 93 swabs were analysed using Polymerase Chain Reaction (PCR) real-time analysis. PCR analysis showed 6 positive (1 excluded), 4 equivocal and 83 negative results for infection with Bd. Equivocal results were assumed to be negative using the precautionary principle. The 5 positive results consisted of 4 emerging (Gosner stage 43-45) metamorphs and 1 adult M. fasciolatus. Fisher's exact test on prevalence showed that the prevalence was significantly different between life stages. All positive results were sampled at high altitudes (790 m); however prevalence was not significantly different between altitudes. Infection of emerging metamorphs suggests that individuals were infected as tadpoles. We hypothesise that M. fasciolatus tadpoles carry Bd through seasons. Thus, Mixophyes

  2. Apoptosis and the selective survival of host animals following thermal bleaching in zooxanthellate corals.

    PubMed

    Tchernov, Dan; Kvitt, Hagit; Haramaty, Liti; Bibby, Thomas S; Gorbunov, Maxim Y; Rosenfeld, Hanna; Falkowski, Paul G

    2011-06-14

    During the past several decades, numerous reports from disparate geographical areas have documented an increased frequency of "bleaching" in reef-forming corals. The phenomenon, triggered by increased sea surface temperatures, occurs when the cnidarian hosts digest and/or expel their intracellular, photosynthetic dinoflagellate symbionts ("zooxanthellae" in the genus Symbiodinium). Although coral bleaching is often followed by the death of the animal hosts, in some cases, the animal survives and can be repopulated with viable zooxanthellae. The physiological factors determining the ability of the coral to survive bleaching events are poorly understood. In this study, we experimentally established that bleaching and death of the host animal involve a caspase-mediated apoptotic cascade induced by reactive oxygen species produced primarily by the algal symbionts. In addition, we demonstrate that, although some corals naturally suppress caspase activity and significantly reduce caspase concentration under high temperatures as a mechanism to prevent colony death from apoptosis, even sensitive corals can be prevented from dying by application of exogenous inhibitors of caspases. Our results indicate that variability in response to thermal stress in corals is determined by a four-element, combinatorial genetic matrix intrinsic to the specific symbiotic association. Based on our experimental data, we present a working model in which the phenotypic expression of this symbiont/host relationship places a selective pressure on the symbiotic association. The model predicts the survival of the host animals in which the caspase-mediated apoptotic cascade is down-regulated.

  3. Molecular Identification and Polymorphism Determination of Cutaneous and Visceral Leishmaniasis Agents Isolated from Human and Animal Hosts in Iran

    PubMed Central

    Mohebali, Mehdi; Mamishi, Setareh; Vasigheh, Farzaneh; Oshaghi, Mohammad Ali; Naddaf, Saied Reza; Teimouri, Aref; Edrissian, Gholam Hossein; Zarei, Zabiholah

    2013-01-01

    Amplification of internal transcript spacer 1 of ribosomal RNA (ITS1-RNA) gene followed by RFLP analysis and sequencing was used to identify the causing agents of cutaneous and visceral leishmaniasis (CL and VL) in humans and animal reservoir hosts from various geographical areas in Iran. We also used random amplified polymorphic DNA (RAPD-PCR) to obtain polymorphisms among isolates of Leishmania spp. Totally, 362 suspected human and animal cases including 173 CL, 49 VL, 60 rodents, and 80 domestic dogs were examined for Leishmania infection. From 112 culture-positive samples prepared from CL cases, 75 (67%) were infected with L. major and 37 (33%) with L. tropica. Of the 60 rodents examined, 25 (41.6%) harbored the Leishmania infection; 21 were infected with L. major and 4 with L. turanica. From 49 suspected VL, 29 were positive by direct agglutination test (DAT), whereas microscopy detected parasite in bone marrow of 25 and culture in 28 of the patients. Two VL patients were infected with L. tropica and 26 with L. infantum. Of the 80 domestic dogs, 56 showed anti-Leishmania antibodies with DAT. Of these, 55 were positive by both microscopy and culture. Molecular identity, obtained only for 47 samples, revealed L. infantum in 43 and L. tropica in 4 dogs. The polymorphisms among L. tropica and L. major isolates were 3.6% and 7.3%; the rate among human and canine VL isolates was 2.8% and 9.8%, respectively. Our results showed that at least four different Leishmania species with various polymorphisms circulate among humans and animal hosts in Iran. PMID:24286085

  4. Swine and rabbits are the main reservoirs of hepatitis E virus in China: detection of HEV RNA in feces of farmed and wild animals.

    PubMed

    Xia, Junke; Zeng, Hang; Liu, Lin; Zhang, Yulin; Liu, Peng; Geng, Jiabao; Wang, Lin; Wang, Ling; Zhuang, Hui

    2015-11-01

    Hepatitis E virus (HEV) infection is recognized as a zoonosis. The prevalence of HEV RNA and anti-HEV antibodies in many animal species has been reported, but the host range of HEV is unclear. The aims of this study were to investigate HEV infection in various animal species and to determine the reservoirs of HEV. Eight hundred twenty-two fecal samples from 17 mammal species and 67 fecal samples from 24 avian species were collected in China and tested for HEV RNA by RT-nPCR. The products of PCR were sequenced and analyzed phylogenetically. The positive rates of HEV RNA isolated from pigs in Beijing, Shandong, and Henan were 33%, 30%, and 92%, respectively, and that from rabbits in Beijing was 5%. HEV RNA was not detectable in farmed foxes, sheep or sika deer, or in wild animals in zoos, including wild boars, yaks, camels, Asiatic black bears, African lions, red pandas, civets, wolves, jackals and primates. Sequence analysis revealed that swine isolates had 97.8%-98.4% nucleotide sequence identity to genotype 4d isolates from patients in Shandong and Jiangsu of China. Phylogenetic analysis showed that swine HEV isolates belong to genotype 4, including subgenotype 4h in Henan and 4d in Beijing and Shandong. The rabbit HEV strains shared 93%-99% nucleotide sequence identity with rabbit strains isolated from Inner Mongolia. In conclusion, swine and rabbits have been confirmed to be the main reservoirs of HEV in China.

  5. Common Origins and Host-Dependent Diversity of Plant and Animal Viromes

    PubMed Central

    Dolja, Valerian V.; Koonin, Eugene V.

    2012-01-01

    Many viruses infecting animals and plants share common cores of homologous genes involved in the key processes of viral replication. In contrast, genes that mediate virus – host interactions including in many cases capsid protein genes are markedly different. There are three distinct scenarios for the origin of related viruses of plants and animals: i) evolution from a common ancestral virus predating the divergence of plants and animals; ii) horizontal transfer of viruses, for example, through insect vectors; iii) parallel origin from related genetic elements. We present evidence that each of these scenarios contributed, to a varying extent, to the evolution of different groups of viruses. PMID:22408703

  6. Dinucleotide Composition in Animal RNA Viruses Is Shaped More by Virus Family than by Host Species.

    PubMed

    Di Giallonardo, Francesca; Schlub, Timothy E; Shi, Mang; Holmes, Edward C

    2017-04-15

    Viruses use the cellular machinery of their hosts for replication. It has therefore been proposed that the nucleotide and dinucleotide compositions of viruses should match those of their host species. If this is upheld, it may then be possible to use dinucleotide composition to predict the true host species of viruses sampled in metagenomic surveys. However, it is also clear that different taxonomic groups of viruses tend to have distinctive patterns of dinucleotide composition that may be independent of host species. To determine the relative strength of the effect of host versus virus family in shaping dinucleotide composition, we performed a comparative analysis of 20 RNA virus families from 15 host groupings, spanning two animal phyla and more than 900 virus species. In particular, we determined the odds ratios for the 16 possible dinucleotides and performed a discriminant analysis to evaluate the capability of virus dinucleotide composition to predict the correct virus family or host taxon from which it was isolated. Notably, while 81% of the data analyzed here were predicted to the correct virus family, only 62% of these data were predicted to their correct subphylum/class host and a mere 32% to their correct mammalian order. Similarly, dinucleotide composition has a weak predictive power for different hosts within individual virus families. We therefore conclude that dinucleotide composition is generally uniform within a virus family but less well reflects that of its host species. This has obvious implications for attempts to accurately predict host species from virus genome sequences alone.IMPORTANCE Determining the processes that shape virus genomes is central to understanding virus evolution and emergence. One question of particular importance is why nucleotide and dinucleotide frequencies differ so markedly between viruses. In particular, it is currently unclear whether host species or virus family has the biggest impact on dinucleotide frequencies and

  7. The role of animal reservoirs in social-environmental landscapes: remarks on the control of avian influenza and preparedness for pandemics.

    PubMed

    Ortiz-Rodríguez, M P; Ramírez-Nieto, G C; Villamil-Jiménez, L C

    2016-12-01

    Influenza viruses are well known for their ability to infect and cause disease in a broad range of hosts. Modern advances in reverse genetics have enabled scientists to probe the mutations that allow influenza viruses to perform host switching. Despite this detailed understanding of the molecular modifications that allow host switching and adaptation, there is a gap in knowledge regarding the factors external to the virus and their interactions that act as triggers leading to a pandemic. Studies on the ecology of zoonotic pathogens should be the new paradigm for understanding not only influenza viruses but any other infectious disease that can be a threat to animal and human health. The literature regarding influenza pandemics and influenza virus reservoirs was reviewed to analyse how social and economic changes can influence the appearance of new outbreaks of influenza. In addition, the importance of new research in a dynamic environment driven by the expansion of human territories and animal production systems is highlighted. A new paradigm is proposed for novel research approaches to infectious diseases such as influenza.

  8. The Impact of Fusarium Mycotoxins on Human and Animal Host Susceptibility to Infectious Diseases

    PubMed Central

    Antonissen, Gunther; Martel, An; Pasmans, Frank; Ducatelle, Richard; Verbrugghe, Elin; Vandenbroucke, Virginie; Li, Shaoji; Haesebrouck, Freddy; Van Immerseel, Filip; Croubels, Siska

    2014-01-01

    Contamination of food and feed with mycotoxins is a worldwide problem. At present, acute mycotoxicosis caused by high doses is rare in humans and animals. Ingestion of low to moderate amounts of Fusarium mycotoxins is common and generally does not result in obvious intoxication. However, these low amounts may impair intestinal health, immune function and/or pathogen fitness, resulting in altered host pathogen interactions and thus a different outcome of infection. This review summarizes the current state of knowledge about the impact of Fusarium mycotoxin exposure on human and animal host susceptibility to infectious diseases. On the one hand, exposure to deoxynivalenol and other Fusarium mycotoxins generally exacerbates infections with parasites, bacteria and viruses across a wide range of animal host species. Well-known examples include coccidiosis in poultry, salmonellosis in pigs and mice, colibacillosis in pigs, necrotic enteritis in poultry, enteric septicemia of catfish, swine respiratory disease, aspergillosis in poultry and rabbits, reovirus infection in mice and Porcine Reproductive and Respiratory Syndrome Virus infection in pigs. However, on the other hand, T-2 toxin has been shown to markedly decrease the colonization capacity of Salmonella in the pig intestine. Although the impact of the exposure of humans to Fusarium toxins on infectious diseases is less well known, extrapolation from animal models suggests possible exacerbation of, for instance, colibacillosis and salmonellosis in humans, as well. PMID:24476707

  9. Climate variability, animal reservoir and transmission of scrub typhus in Southern China

    PubMed Central

    Li, Xiaoning; Ma, Yu; Tao, Xia; Wu, Xinwei

    2017-01-01

    Objectives We aimed to evaluate the relationships between climate variability, animal reservoirs and scrub typhus incidence in Southern China. Methods We obtained data on scrub typhus cases in Guangzhou every month from 2006 to 2014 from the Chinese communicable disease network. Time-series Poisson regression models and distributed lag nonlinear models (DLNM) were used to evaluate the relationship between risk factors and scrub typhus. Results Wavelet analysis found the incidence of scrub typhus cycled with a period of approximately 8–12 months and long-term trends with a period of approximately 24–36 months. The DLNM model shows that relative humidity, rainfall, DTR, MEI and rodent density were associated with the incidence of scrub typhus. Conclusions Our findings suggest that the incidence scrub typhus has two main temporal cycles. Determining the reason for this trend and how it can be used for disease control and prevention requires additional research. The transmission of scrub typhus is highly dependent on climate factors and rodent density, both of which should be considered in prevention and control strategies for scrub typhus. PMID:28273079

  10. Subcutaneous implants for long-acting drug therapy in laboratory animals may generate unintended drug reservoirs

    PubMed Central

    Guarnieri, Michael; Tyler, Betty M.; DeTolla, Louis; Zhao, Ming; Kobrin, Barry

    2014-01-01

    Background: Long-acting therapy in laboratory animals offers advantages over the current practice of 2-3 daily drug injections. Yet little is known about the disintegration of biodegradable drug implants in rodents. Objective: Compare bioavailability of buprenorphine with the biodegradation of lipid-encapsulated subcutaneous drug pellets. Methods: Pharmacokinetic and histopathology studies were conducted in BALB/c female mice implanted with cholesterol-buprenorphine drug pellets. Results: Drug levels are below the level of detection (0.5 ng/mL plasma) within 4-5 days of implant. However, necroscopy revealed that interstitial tissues begin to seal implants within a week. Visual inspection of the implant site revealed no evidence of inflammation or edema associated with the cholesterol-drug residue. Chemical analyses demonstrated that the residues contained 10-13% of the initial opiate dose for at least two weeks post implant. Discussion: The results demonstrate that biodegradable scaffolds can become sequestered in the subcutaneous space. Conclusion: Drug implants can retain significant and unintended reservoirs of drugs. PMID:24459402

  11. Treponemes Detected in Digital Dermatitis Lesions in Brazilian Dairy Cattle and Possible Host Reservoirs of Infection

    PubMed Central

    Nascimento, Ligia Valéria; Mauerwerk, Marlise Teresinha; dos Santos, Cibelli Lopes; de Barros Filho, Ivan Roque; Birgel Júnior, Eduardo Harry; Madeira, Humberto Maciel França

    2015-01-01

    The main pathogenic treponemes causing bovine digital dermatitis were identified from 17 infected herds in southern Brazil for the first time in this study using PCR. We did not find a relationship between treponeme phylogroup composition and clinical classification. Treponema phagedenis was present in all lesions. Rumen fluid was implicated as a reservoir location for these pathogens. PMID:25788552

  12. Staphylococcus aureus host specificity: comparative genomics of human versus animal isolates by multi-strain microarray.

    PubMed

    Sung, Julia M-L; Lloyd, David H; Lindsay, Jodi A

    2008-07-01

    Staphylococcus aureus is a commensal and pathogen of several mammalian species, particularly humans and cattle. We aimed to (i) identify S. aureus genes associated with host specificity, (ii) determine the relatedness of human and animal isolates, and (iii) identify whether human and animal isolates typically exchanged mobile genetic elements encoding virulence and resistance genes. Using a well-validated seven-strain S. aureus microarray, we compared 56 UK S. aureus isolates that caused infection in cows, horses, goats, sheep and a camel with 161 human S. aureus isolates from healthy carriers and community acquired infections in the UK. We had previously shown that human isolates are clustered into ten dominant and a few minor lineages, each with unique combinations of surface proteins predicted to bind to human proteins. We found that the animal-associated S. aureus clustered into ten lineages, with 61 % assigned to four lineages, ST151, ST771, ST130 and ST873, that were unique to animals. The majority of bovine mastitis was caused by isolates of lineage ST151, ST771 and ST97, but a few human lineages also caused mastitis. S. aureus isolated from horses were more likely to cluster into human-associated lineages, with 54 % of horse-associated S. aureus assigned to the human clusters CC1, CC8 and CC22; along with the presence of some multi-drug resistant strains, this suggests a human origin. This is the most comprehensive genetic comparison of human versus animal S. aureus isolates conducted, and because we used a whole-genome approach we could estimate the key genes with the greatest variability that are associated with host specificity. Several genes conserved in all human isolates were variable or missing in one or more animal lineages, including the well-characterized lineage specific genes fnbA, fnbB and coa. Interestingly, genes carried on mobile genetic elements (MGEs) such as chp, scn and sak were less common in animal S. aureus isolates, and bap was not

  13. Evolution of hantaviruses: co-speciation with reservoir hosts for more than 100 MYR.

    PubMed

    Plyusnin, Alexander; Sironen, Tarja

    2014-07-17

    The most recent (9th) Report of the International Committee on Taxonomy of Viruses (ICTV) lists 23 established and 30 provisional species in the genus Hantavirus (family Bunyaviridae) (Plyusnin et al., 2012). These virus species are harbored by altogether 51 species of rodents, shrews and moles and thus in most cases it is a relationship of "one hantavirus-one host". Such a tight bond between the two, in combination with the observed association between whole groups of hantaviruses and (sub)families of rodents, helped to develop the widely accepted view of a long-term co-evolution (co-speciation) of these viruses with their hosts. Accumulating evidence of host-switching events, both recent and ancient, however challenged some of the earlier views on hantavirus evolution. In this paper we discuss the concept of hantavirus-host co-speciation and propose a scenario of hantavirus evolution based on the currently available genetic information. This scenario is based on the hypothesis that hantaviruses are very ancient viruses which already existed at the estimated diversification point of major placental clades, of which one includes the ancestors of the order Rodentia and another the ancestors of both orders Eulipotyphla and Chiroptera; the diversification occurred approximately at 90-100 MYA. We also speculate that the evolutionary history of hantaviruses extents even deeper in the past, beyond this time-point, and included the transmission of a (pre)bunyavirus from an insect host to a mammal host.

  14. Shedding dynamics of Morogoro virus, an African arenavirus closely related to Lassa virus, in its natural reservoir host Mastomys natalensis.

    PubMed

    Borremans, Benny; Vossen, Raphaël; Becker-Ziaja, Beate; Gryseels, Sophie; Hughes, Nelika; Van Gestel, Mats; Van Houtte, Natalie; Günther, Stephan; Leirs, Herwig

    2015-05-29

    Arenaviruses can cause mild to severe hemorrhagic fevers. Humans mainly get infected through contact with infected rodents or their excretions, yet little is known about transmission dynamics within rodent populations. Morogoro virus (MORV) is an Old World arenavirus closely related to Lassa virus with which it shares the same host species Mastomys natalensis. We injected MORV in its host, and sampled blood and excretions at frequent intervals. Infection in adults was acute; viral RNA disappeared from blood after 18 days post infection (dpi) and from excretions after 39 dpi. Antibodies were present from 7 dpi and never disappeared. Neonatally infected animals acquired a chronic infection with RNA and antibodies in blood for at least 3 months. The quantified excretion and antibody patterns can be used to inform mathematical transmission models, and are essential for understanding and controlling transmission in the natural rodent host populations.

  15. Shedding dynamics of Morogoro virus, an African arenavirus closely related to Lassa virus, in its natural reservoir host Mastomys natalensis

    PubMed Central

    Borremans, Benny; Vossen, Raphaël; Becker-Ziaja, Beate; Gryseels, Sophie; Hughes, Nelika; Van Gestel, Mats; Van Houtte, Natalie; Günther, Stephan; Leirs, Herwig

    2015-01-01

    Arenaviruses can cause mild to severe hemorrhagic fevers. Humans mainly get infected through contact with infected rodents or their excretions, yet little is known about transmission dynamics within rodent populations. Morogoro virus (MORV) is an Old World arenavirus closely related to Lassa virus with which it shares the same host species Mastomys natalensis. We injected MORV in its host, and sampled blood and excretions at frequent intervals. Infection in adults was acute; viral RNA disappeared from blood after 18 days post infection (dpi) and from excretions after 39 dpi. Antibodies were present from 7 dpi and never disappeared. Neonatally infected animals acquired a chronic infection with RNA and antibodies in blood for at least 3 months. The quantified excretion and antibody patterns can be used to inform mathematical transmission models, and are essential for understanding and controlling transmission in the natural rodent host populations. PMID:26022445

  16. Animal Models to Study Host-Bacteria Interactions Involved in Periodontitis

    PubMed Central

    Graves, Dana T.; Kang, Jun; Andriankaja, Oelisoa; Wada, Keisuke; Rossa, Carlos

    2013-01-01

    Animal models have distinct advantages because they can mimic cellular complexities that occur in humans in vivo and are often more accurate than in vitro studies that take place on plastic surfaces with limited numbers of cell types present. Furthermore, cause and effect relationships can be established by applying inhibitors or activators or through the use of genetically modified animals. Such gain or loss of function studies are often difficult to achieve in human clinical studies, particularly in obtaining target tissue due to important ethical considerations. Animal models in periodontal disease are particularly important at this point in the development of the scientific basis for understanding the predominant pathological processes. Periodontal disease can be broken down into discrete steps, each of which may be studied separately depending upon the animal model. These steps involve the development of a pathogenic biofilm, invasion of connective tissue by bacteria or their products, induction of a destructive host response in connective tissue and limitation of a repair process that follows tissue breakdown. Animal studies can test hypotheses related to each of these steps, and should be evaluated by their capacity to test a specific hypothesis rather than recapitulating all aspects of periodontal disease. Thus, each of the models described below can be adapted to test discrete components of the pathological process of periodontal disease, but not necessarily all of them. PMID:22142960

  17. A light carbon reservoir recorded in zircon-hosted diamond from the Jack Hills.

    PubMed

    Nemchin, Alexander A; Whitehouse, Martin J; Menneken, Martina; Geisler, Thorsten; Pidgeon, Robert T; Wilde, Simon A

    2008-07-03

    The recent discovery of diamond-graphite inclusions in the Earth's oldest zircon grains (formed up to 4,252 Myr ago) from the Jack Hills metasediments in Western Australia provides a unique opportunity to investigate Earth's earliest known carbon reservoir. Here we report ion microprobe analyses of the carbon isotope composition of these diamond-graphite inclusions. The observed delta(13)C(PDB) values (expressed using the PeeDee Belemnite standard) range between -5 per mil and -58 per mil with a median of -31 per mil. This extends beyond typical mantle values of around -6 per mil to values observed in metamorphic and some eclogitic diamonds that are interpreted to reflect deep subduction of low-delta(13)C(PDB) biogenic surface carbon. Low delta(13)C(PDB) values may also be produced by inorganic chemical reactions, and therefore are not unambiguous evidence for life on Earth as early as 4,250 Myr ago. Regardless, our results suggest that a low-delta(13)C(PDB) reservoir may have existed on the early Earth.

  18. Pathogenic landscapes: Interactions between land, people, disease vectors, and their animal hosts

    PubMed Central

    2010-01-01

    Background Landscape attributes influence spatial variations in disease risk or incidence. We present a review of the key findings from eight case studies that we conducted in Europe and West Africa on the impact of land changes on emerging or re-emerging vector-borne diseases and/or zoonoses. The case studies concern West Nile virus transmission in Senegal, tick-borne encephalitis incidence in Latvia, sandfly abundance in the French Pyrenees, Rift Valley Fever in the Ferlo (Senegal), West Nile Fever and the risk of malaria re-emergence in the Camargue, and rodent-borne Puumala hantavirus and Lyme borreliosis in Belgium. Results We identified general principles governing landscape epidemiology in these diverse disease systems and geographic regions. We formulated ten propositions that are related to landscape attributes, spatial patterns and habitat connectivity, pathways of pathogen transmission between vectors and hosts, scale issues, land use and ownership, and human behaviour associated with transmission cycles. Conclusions A static view of the "pathogenecity" of landscapes overlays maps of the spatial distribution of vectors and their habitats, animal hosts carrying specific pathogens and their habitat, and susceptible human hosts and their land use. A more dynamic view emphasizing the spatial and temporal interactions between these agents at multiple scales is more appropriate. We also highlight the complementarity of the modelling approaches used in our case studies. Integrated analyses at the landscape scale allows a better understanding of interactions between changes in ecosystems and climate, land use and human behaviour, and the ecology of vectors and animal hosts of infectious agents. PMID:20979609

  19. Does influenza A virus infection affect movement behaviour during stopover in its wild reservoir host?

    PubMed Central

    Bengtsson, Daniel; Safi, Kamran; Avril, Alexis; Fiedler, Wolfgang; Wikelski, Martin; Gunnarsson, Gunnar; Elmberg, Johan; Tolf, Conny; Olsen, Björn; Waldenström, Jonas

    2016-01-01

    The last decade has seen a surge in research on avian influenza A viruses (IAVs), in part fuelled by the emergence, spread and potential zoonotic importance of highly pathogenic virus subtypes. The mallard (Anas platyrhynchos) is the most numerous and widespread dabbling duck in the world, and one of the most important natural hosts for studying IAV transmission dynamics. In order to predict the likelihood of IAV transmission between individual ducks and to other hosts, as well as between geographical regions, it is important to understand how IAV infection affects the host. In this study, we analysed the movements of 40 mallards equipped with GPS transmitters and three-dimensional accelerometers, of which 20 were naturally infected with low pathogenic avian influenza virus (LPAIV), at a major stopover site in the Northwest European flyway. Movements differed substantially between day and night, as well as between mallards returning to the capture site and those feeding in natural habitats. However, movement patterns did not differ between LPAIV infected and uninfected birds. Hence, LPAIV infection probably does not affect mallard movements during stopover, with high possibility of virus spread along the migration route as a consequence. PMID:26998334

  20. Ecological Connectivity of Trypanosoma cruzi Reservoirs and Triatoma pallidipennis Hosts in an Anthropogenic Landscape with Endemic Chagas Disease

    PubMed Central

    Ramsey, Janine M.; Gutiérrez-Cabrera, Ana E.; Salgado-Ramírez, Liliana; Peterson, A. Townsend; Sánchez-Cordero, Victor; Ibarra-Cerdeña, Carlos N.

    2012-01-01

    Traditional methods for Chagas disease prevention are targeted at domestic vector reduction, as well as control of transfusion and maternal-fetal transmission. Population connectivity of Trypanosoma cruzi-infected vectors and hosts, among sylvatic, ecotone and domestic habitats could jeopardize targeted efforts to reduce human exposure. This connectivity was evaluated in a Mexican community with reports of high vector infestation, human infection, and Chagas disease, surrounded by agricultural and natural areas. We surveyed bats, rodents, and triatomines in dry and rainy seasons in three adjacent habitats (domestic, ecotone, sylvatic), and measured T. cruzi prevalence, and host feeding sources of triatomines. Of 12 bat and 7 rodent species, no bat tested positive for T. cruzi, but all rodent species tested positive in at least one season or habitat. Highest T. cruzi infection prevalence was found in the rodents, Baiomys musculus and Neotoma mexicana. In general, parasite prevalence was not related to habitat or season, although the sylvatic habitat had higher infection prevalence than by chance, during the dry season. Wild and domestic mammals were identified as bloodmeals of T. pallidipennis, with 9% of individuals having mixed human (4.8% single human) and other mammal species in bloodmeals, especially in the dry season; these vectors tested >50% positive for T. cruzi. Overall, ecological connectivity is broad across this matrix, based on high rodent community similarity, vector and T. cruzi presence. Cost-effective T. cruzi, vector control strategies and Chagas disease transmission prevention will need to consider continuous potential for parasite movement over the entire landscape. This study provides clear evidence that these strategies will need to include reservoir/host species in at least ecotones, in addition to domestic habitats. PMID:23049923

  1. Dingoes (Canis dingo Meyer, 1793) continue to be an important reservoir host of Dirofilaria immitis in low density housing areas in Australia.

    PubMed

    Smout, Felicity A; Skerratt, Lee F; Butler, James R A; Johnson, Christopher N; Congdon, Bradley C

    2016-01-15

    Heartworm (Dirofilaria immitis) is a parasitic nematode responsible for canine and feline cardiopulmonary dirofilariasis and human zoonotic filariosis in both tropical and temperate regions throughout the world. Importantly, this study in the Wet Tropics of Far North Queensland found D. immitis remains at high prevalence (72.7%) in wild dingoes in low density housing areas in Australia. This prevalence is equivalent to the highest levels seen in wild dogs in Australia and represents an ongoing risk to domestic dogs, cats and humans. In contrast, in higher density residential areas prevalence was significantly lower (16.7%, p=0.001). It is possible that chemotherapeutic heartworm (HW) prevention in domestic dogs in these higher density housing areas is helping to control infection in the resident dingo population. Five dingoes killed in council control operations around Atherton, a non-endemic HW region in the Wet Tropics, were all negative for HW likely due to the colder climate of the region restricting transmission of the disease. This survey highlights the importance of dingoes as reservoir hosts of HW disease and that the subsequent risk of infection to companion animals and humans depends on local factors such as housing density, possibly linked to chemotherapeutic HW control in domestic dogs and climate. Our findings show that veterinary clinicians need to ensure that pet owners are aware of HW disease and do not become complacent about HW chemoprohylaxis in areas which support dingo populations.

  2. Entry of oomycete and fungal effectors into plant and animal host cells.

    PubMed

    Kale, Shiv D; Tyler, Brett M

    2011-12-01

    Fungal and oomycete pathogens cause many destructive diseases of plants and important diseases of humans and other animals. Fungal and oomycete plant pathogens secrete numerous effector proteins that can enter inside host cells to condition susceptibility. Until recently it has been unknown if these effectors enter via pathogen-encoded translocons or via pathogen-independent mechanisms. Here we review recent evidence that many fungal and oomycete effectors enter via receptor-mediated endocytosis, and can do so in the absence of the pathogen. Surprisingly, a large number of these effectors utilize cell surface phosphatidyinositol-3-phosphate (PI-3-P) as a receptor, a molecule previously known only inside cells. Binding of effectors to PI-3-P appears to be mediated by the cell entry motif RXLR in oomycetes, and by diverse RXLR-like variants in fungi. PI-3-P appears to be present on the surface of animal cells also, suggesting that it may mediate entry of effectors of fungal and oomycete animal pathogens, for example, RXLR effectors found in the oomycete fish pathogen, Saprolegnia parasitica. Reagents that can block PI-3-P-mediated entry have been identified, suggesting new therapeutic strategies.

  3. Wild boar (Sus scrofa) - reservoir host of Toxoplasma gondii, Neospora caninum and Anaplasma phagocytophilum in Slovakia.

    PubMed

    Reiterová, Katarína; Špilovská, Silvia; Blaňarová, Lucia; Derdáková, Markéta; Čobádiová, Andrea; Hisira, Vladimír

    2016-03-01

    In Central Europe the wild boar population is permanently growing and consequently Cf foodborne infections. In this study serological and molecular detection of Toxoplasma gondii and Neospora caninum in wild boars was evaluated. Moreover, same samples were screened for the presence and genetic variability of tick-borne bacterium Anaplasma phagocytophilum. Blood samples collected from 113 wild boars from Southern Slovakia were examined for antibodies to T. gondii by indirect and to N. caninum by competitive ELISA. The presence of parasitic DNA in blood samples was determined by standard or real time PCR techniques. Antibodies against T. gondii and N. caninum were detected in 45 (39.8%) and 38 (33.6%) animals, respectively. Females were more frequently infected for both pathogens than males. The high seropositivity against both coccidia indicates a permanent occurrence of these pathogens in the studied locality. T. gondii DNA was confirmed in five seropositive boars (4.4%) and N. caninum in 23 blood samples (20.4%). Three out of 23 N. caninum PCR positive animals did not show seropositivity. Three out of 113 blood samples of wild boars were positive for A. phagocytophilum (2.7%). The obtained A. phagocytophilum sequences were 100% identical with GenBankTM isolates from Slovak dog (KC985242); German horse (JF893938) or wild boar (EF143810) and red deer (EF143808) from Poland. Coinfections of T. gondii with N. caninum and N. caninum with A. phagocytophilum were detected in single cases. Results suggest a potential zoonotic risk of toxoplasmosis transmission to humans and the spread of neosporosis to farm animals.

  4. Potential Animal Reservoirs of Toscana Virus and Coinfections with Leishmania infantum in Turkey

    PubMed Central

    Dincer, Ender; Gargari, Sepandar; Ozkul, Aykut; Ergunay, Koray

    2015-01-01

    Toscana virus (TOSV), a sandfly-borne phlebovirus, is an important agent of human meningoencephalitis in the Mediterranean region, for which vertebrates acting as reservoirs have not yet been determined. This study investigates TOSV and Leishmania infections in dogs, cats, sheep, and goats from Adana and Mersin provinces in southeastern Turkey. TOSV neutralizing antibodies were demonstrated in 40.4% of the dog and 4% of the goat samples. TOSV RNA was detected in 9.9% of the 252 samples that mainly comprise dogs (96%). Thus, canine species can be suggested as the candidate reservoirs of TOSV. Partial sequences revealed the activity of TOSV genotypes A and B. In two dogs presenting with symptoms of canine leishmaniasis, infections of TOSV genotype B and Leishmania infantum have been documented, describing the first report of coinfections with these agents. PMID:25711610

  5. Isolation of Ehrlichia chaffeensis from wild white-tailed deer (Odocoileus virginianus) confirms their role as natural reservoir hosts.

    PubMed

    Lockhart, J M; Davidson, W R; Stallknecht, D E; Dawson, J E; Howerth, E W

    1997-07-01

    Field and experimental studies have implicated white-tailed deer (Odocoileus virginianus) as probable reservoir hosts for Ehrlichia chaffeensis, the causative agent of human monocytic ehrlichiosis, but natural infection in deer has not been confirmed through isolation of E. chaffeensis. Thirty-five white-tailed deer collected from three Amblyomma americanum-infested populations in Georgia were examined for evidence of E. chaffeensis infection by serologic, molecular, cell culture, and xenodiagnostic methods. Twenty-seven deer (77%) had E. chaffeensis-reactive indirect fluorescent-antibody assay titers of > or = 1:64; and the blood, spleens, or lymph nodes of seven (20%) deer were positive in a nested PCR assay with E. chaffeensis-specific primers. E. chaffeensis was isolated in DH82 cell cultures from the blood of five (14%) deer, including two deer that were PCR negative. Combination of culture and PCR results indicated that six (17%) deer were probably rickettsemic and that nine (26%) were probably infected. Restriction digestion of PCR products amplified from deer tissues and cell culture isolates resulted in a banding pattern consistent with the E. chaffeensis 16S rRNA gene sequence. The sequences of all PCR products from deer tissues or cell culture isolates were identical to the sequence of the Arkansas type strain of E. chaffeensis. Xenodiagnosis with C3H mice inoculated intraperitoneally with deer blood, spleen, or lymph node suspensions was unsuccessful. When viewed in the context of previous studies, these findings provide strong evidence that E. chaffeensis is maintained in nature primarily by a tick vector-vertebrate reservoir system consisting of lone star ticks and white-tailed deer.

  6. External lipid PI3P mediates entry of eukaryotic pathogen effectors into plant and animal host cells.

    PubMed

    Kale, Shiv D; Gu, Biao; Capelluto, Daniel G S; Dou, Daolong; Feldman, Emily; Rumore, Amanda; Arredondo, Felipe D; Hanlon, Regina; Fudal, Isabelle; Rouxel, Thierry; Lawrence, Christopher B; Shan, Weixing; Tyler, Brett M

    2010-07-23

    Pathogens of plants and animals produce effector proteins that are transferred into the cytoplasm of host cells to suppress host defenses. One type of plant pathogens, oomycetes, produces effector proteins with N-terminal RXLR and dEER motifs that enable entry into host cells. We show here that effectors of another pathogen type, fungi, contain functional variants of the RXLR motif, and that the oomycete and fungal RXLR motifs enable binding to the phospholipid, phosphatidylinositol-3-phosphate (PI3P). We find that PI3P is abundant on the outer surface of plant cell plasma membranes and, furthermore, on some animal cells. All effectors could also enter human cells, suggesting that PI3P-mediated effector entry may be very widespread in plant, animal and human pathogenesis. Entry into both plant and animal cells involves lipid raft-mediated endocytosis. Blocking PI3P binding inhibited effector entry, suggesting new therapeutic avenues.

  7. Spatio-temporal Analysis of the Genetic Diversity of Arctic Rabies Viruses and Their Reservoir Hosts in Greenland

    PubMed Central

    Hanke, Dennis; Freuling, Conrad M.; Fischer, Susanne; Hueffer, Karsten; Hundertmark, Kris; Nadin-Davis, Susan; Marston, Denise; Fooks, Anthony R.; Bøtner, Anette; Mettenleiter, Thomas C.; Beer, Martin; Rasmussen, Thomas B.; Müller, Thomas F.; Höper, Dirk

    2016-01-01

    There has been limited knowledge on spatio-temporal epidemiology of zoonotic arctic fox rabies among countries bordering the Arctic, in particular Greenland. Previous molecular epidemiological studies have suggested the occurrence of one particular arctic rabies virus (RABV) lineage (arctic-3), but have been limited by a low number of available samples preventing in-depth high resolution phylogenetic analysis of RABVs at that time. However, an improved knowledge of the evolution, at a molecular level, of the circulating RABVs and a better understanding of the historical perspective of the disease in Greenland is necessary for better direct control measures on the island. These issues have been addressed by investigating the spatio-temporal genetic diversity of arctic RABVs and their reservoir host, the arctic fox, in Greenland using both full and partial genome sequences. Using a unique set of 79 arctic RABV full genome sequences from Greenland, Canada, USA (Alaska) and Russia obtained between 1977 and 2014, a description of the historic context in relation to the genetic diversity of currently circulating RABV in Greenland and neighboring Canadian Northern territories has been provided. The phylogenetic analysis confirmed delineation into four major arctic RABV lineages (arctic 1–4) with viruses from Greenland exclusively grouping into the circumpolar arctic-3 lineage. High resolution analysis enabled distinction of seven geographically distinct subclades (3.I – 3.VII) with two subclades containing viruses from both Greenland and Canada. By combining analysis of full length RABV genome sequences and host derived sequences encoding mitochondrial proteins obtained simultaneously from brain tissues of 49 arctic foxes, the interaction of viruses and their hosts was explored in detail. Such an approach can serve as a blueprint for analysis of infectious disease dynamics and virus-host interdependencies. The results showed a fine-scale spatial population structure

  8. Spatio-temporal Analysis of the Genetic Diversity of Arctic Rabies Viruses and Their Reservoir Hosts in Greenland.

    PubMed

    Hanke, Dennis; Freuling, Conrad M; Fischer, Susanne; Hueffer, Karsten; Hundertmark, Kris; Nadin-Davis, Susan; Marston, Denise; Fooks, Anthony R; Bøtner, Anette; Mettenleiter, Thomas C; Beer, Martin; Rasmussen, Thomas B; Müller, Thomas F; Höper, Dirk

    2016-07-01

    There has been limited knowledge on spatio-temporal epidemiology of zoonotic arctic fox rabies among countries bordering the Arctic, in particular Greenland. Previous molecular epidemiological studies have suggested the occurrence of one particular arctic rabies virus (RABV) lineage (arctic-3), but have been limited by a low number of available samples preventing in-depth high resolution phylogenetic analysis of RABVs at that time. However, an improved knowledge of the evolution, at a molecular level, of the circulating RABVs and a better understanding of the historical perspective of the disease in Greenland is necessary for better direct control measures on the island. These issues have been addressed by investigating the spatio-temporal genetic diversity of arctic RABVs and their reservoir host, the arctic fox, in Greenland using both full and partial genome sequences. Using a unique set of 79 arctic RABV full genome sequences from Greenland, Canada, USA (Alaska) and Russia obtained between 1977 and 2014, a description of the historic context in relation to the genetic diversity of currently circulating RABV in Greenland and neighboring Canadian Northern territories has been provided. The phylogenetic analysis confirmed delineation into four major arctic RABV lineages (arctic 1-4) with viruses from Greenland exclusively grouping into the circumpolar arctic-3 lineage. High resolution analysis enabled distinction of seven geographically distinct subclades (3.I - 3.VII) with two subclades containing viruses from both Greenland and Canada. By combining analysis of full length RABV genome sequences and host derived sequences encoding mitochondrial proteins obtained simultaneously from brain tissues of 49 arctic foxes, the interaction of viruses and their hosts was explored in detail. Such an approach can serve as a blueprint for analysis of infectious disease dynamics and virus-host interdependencies. The results showed a fine-scale spatial population structure in

  9. Current and Potential Treatments for Reducing Campylobacter Colonization in Animal Hosts and Disease in Humans

    PubMed Central

    Johnson, Tylor J.; Shank, Janette M.; Johnson, Jeremiah G.

    2017-01-01

    Campylobacter jejuni is the leading cause of bacteria-derived gastroenteritis worldwide. In the developed world, Campylobacter is usually acquired by consuming under-cooked poultry, while in the developing world it is often obtained through drinking contaminated water. Once consumed, the bacteria adhere to the intestinal epithelium or mucus layer, causing toxin-mediated inhibition of fluid reabsorption from the intestine and invasion-induced inflammation and diarrhea. Traditionally, severe or prolonged cases of campylobacteriosis have been treated with antibiotics; however, overuse of these antibiotics has led to the emergence of antibiotic-resistant strains. As the incidence of antibiotic resistance, emergence of post-infectious diseases, and economic burden associated with Campylobacter increases, it is becoming urgent that novel treatments are developed to reduce Campylobacter numbers in commercial poultry and campylobacteriosis in humans. The purpose of this review is to provide the current status of present and proposed treatments to combat Campylobacter infection in humans and colonization in animal reservoirs. These treatments include anti-Campylobacter compounds, probiotics, bacteriophage, vaccines, and anti-Campylobacter bacteriocins, all of which may be successful at reducing the incidence of campylobacteriosis in humans and/or colonization loads in poultry. In addition to reviewing treatments, we will also address several proposed targets that may be used in future development of novel anti-Campylobacter treatments. PMID:28386253

  10. Fitness costs of animal medication: antiparasitic plant chemicals reduce fitness of monarch butterfly hosts.

    PubMed

    Tao, Leiling; Hoang, Kevin M; Hunter, Mark D; de Roode, Jacobus C

    2016-09-01

    The emerging field of ecological immunology demonstrates that allocation by hosts to immune defence against parasites is constrained by the costs of those defences. However, the costs of non-immunological defences, which are important alternatives to canonical immune systems, are less well characterized. Estimating such costs is essential for our understanding of the ecology and evolution of alternative host defence strategies. Many animals have evolved medication behaviours, whereby they use antiparasitic compounds from their environment to protect themselves or their kin from parasitism. Documenting the costs of medication behaviours is complicated by natural variation in the medicinal components of diets and their covariance with other dietary components, such as macronutrients. In the current study, we explore the costs of the usage of antiparasitic compounds in monarch butterflies (Danaus plexippus), using natural variation in concentrations of antiparasitic compounds among plants. Upon infection by their specialist protozoan parasite Ophryocystis elektroscirrha, monarch butterflies can selectively oviposit on milkweed with high foliar concentrations of cardenolides, secondary chemicals that reduce parasite growth. Here, we show that these antiparasitic cardenolides can also impose significant costs on both uninfected and infected butterflies. Among eight milkweed species that vary substantially in their foliar cardenolide concentration and composition, we observed the opposing effects of cardenolides on monarch fitness traits. While high foliar cardenolide concentrations increased the tolerance of monarch butterflies to infection, they reduced the survival rate of caterpillars to adulthood. Additionally, although non-polar cardenolide compounds decreased the spore load of infected butterflies, they also reduced the life span of uninfected butterflies, resulting in a hump-shaped curve between cardenolide non-polarity and the life span of infected butterflies

  11. Attributing foodborne salmonellosis in humans to animal reservoirs in the European Union using a multi-country stochastic model.

    PubMed

    DE Knegt, L V; Pires, S M; Hald, T

    2015-04-01

    A Bayesian modelling approach comparing the occurrence of Salmonella serovars in animals and humans was used to attribute salmonellosis cases to broilers, turkeys, pigs, laying hens, travel and outbreaks in 24 European Union countries. Salmonella data for animals and humans, covering the period from 2007 to 2009, were mainly obtained from studies and reports published by the European Food Safety Authority. Availability of food sources for consumption was derived from trade and production data from the European Statistical Office. Results showed layers as the most important reservoir of human salmonellosis in Europe, with 42·4% (7 903 000 cases, 95% credibility interval 4 181 000-14 510 000) of cases, 95·9% of which was caused by S. Enteritidis. In Finland and Sweden, most cases were travel-related, while in most other countries the main sources were related to the laying hen or pig reservoir, highlighting differences in the epidemiology of Salmonella, surveillance focus and eating habits across the European Union.

  12. Phytophthora ramorum does not cause physiologically significant systemic injury to California bay laurel, its primary reservoir host.

    PubMed

    DiLeo, M V; Bostock, R M; Rizzo, D M

    2009-11-01

    California bay laurel trees (Umbellularia californica) play a crucial role in the reproduction and survival of Phytophthora ramorum in coastal California forests by supporting sporulation during the rainy season and by providing a means for the pathogen to survive the dry, Mediterranean summer. While bay laurel is thus critical to the epidemiology of sudden oak death and other P. ramorum diseases in California, the relatively minor symptoms observed on this reservoir host suggest that it may not sustain ecologically significant injury itself. The long-term role that P. ramorum will play in California forests will depend in part on the extent to which this pathogen decreases the ecological fitness of bay laurel. Despite the importance of this question, no study has yet investigated in detail the physiological impact that ramorum blight imposes on bay laurel. This experimental study quantifies the impact that P. ramorum has on artificially inoculated bay laurel seedlings with measurements that integrate the full injury that infection with an oomycete may cause: photosynthetic efficiency, total photosynthetic area, and growth. Leaf area and leaf mass were not impacted significantly by infection of P. ramorum. Photosynthetic efficiency was mildly depressed in symptomatic, but not asymptomatic leaves, despite unnaturally high levels of necrosis that were imposed on the seedlings. These results demonstrate that bay laurel trees suffer only minor injury from ramorum blight beyond visible necrotic symptoms. Consequently, it is highly likely that bay laurel will continue to be widely available as a host for P. ramorum in California forests, which has long-term implications for the composition of these forests.

  13. New Sylvatic Hosts of Trypanosoma cruzi and Their Reservoir Competence in the Humid Chaco of Argentina: A Longitudinal Study

    PubMed Central

    Orozco, M. Marcela; Enriquez, Gustavo F.; Alvarado-Otegui, Julián A.; Cardinal, M. Victoria; Schijman, Alejandro G.; Kitron, Uriel; Gürtler, Ricardo E.

    2013-01-01

    A four-year longitudinal study of the structure of sylvatic transmission cycles of Trypanosoma cruzi, reservoir host competence and parasite discrete typing units was conducted in a disturbed rural area of the humid Chaco in Argentina. Among 190 mammals examined by xenodiagnosis and polymerase chain reaction amplification, the composite prevalence of infection was substantially higher in Dasypus novemcinctus armadillos (57.7%) and Didelphis albiventris opossums (38.1%) than in Euphractus sexcinctus (20.0%), Tolypeutes matacus (12.5%), and Chaetophractus vellerosus (6.3%) armadillos. Trypanosoma cruzi was detected for the first time in Thylamys pusilla small opossums and in two unidentified small rodents. Infection was spatially aggregated only in armadillos. All Didelphis were infected with T. cruzi I and all armadillo species were infected with T. cruzi III, implying two distinct sylvatic cycles with no inputs from the domestic cycle. Dasypus armadillos and Didelphis opossums were much more infectious to vectors than other armadillos, small opossums, or rodents. PMID:23530075

  14. Satellite imagery characterizes local animal reservoir populations of Sin Nombre virus in the southwestern United States

    PubMed Central

    Glass, Gregory E.; Yates, Terry L.; Fine, Joshua B.; Shields, Timothy M.; Kendall, John B.; Hope, Andrew G.; Parmenter, Cheryl A.; Peters, C. J.; Ksiazek, Thomas G.; Li, Chung-Sheng; Patz, Jonathan A.; Mills, James N.

    2002-01-01

    The relationship between the risk of hantaviral pulmonary syndrome (HPS), as estimated from satellite imagery, and local rodent populations was examined. HPS risk, predicted before rodent sampling, was highly associated with the abundance of Peromyscus maniculatus, the reservoir of Sin Nombre virus (SNV). P. maniculatus were common in high-risk sites, and populations in high-risk areas were skewed toward adult males, the subclass most frequently infected with SNV. In the year after an El Niño Southern Oscillation (ENSO), captures of P. maniculatus increased only in high-risk areas. During 1998, few sites had infected mice, but by 1999, 18/20 of the high-risk sites contained infected mice and the crude prevalence was 30.8%. Only 1/18 of the low-risk sites contained infected rodents, and the prevalence of infection was lower (8.3%). Satellite imagery identified environmental features associated with SNV transmission within its reservoir population, but at least 2 years of high-risk conditions were needed for SNV to reach high prevalence. Areas with persistently high-risk environmental conditions may serve as refugia for the survival of SNV in local mouse populations. PMID:12473747

  15. Satellite imagery characterizes local animal reservoir populations of Sin Nombre virus in the southwestern United States

    USGS Publications Warehouse

    Glass, Gregory E; Yates, Terry L.; Fine, Joshua B.; Shields, Timothy M.; Kendall, John B.; Hope, Andrew G.; Parmenter, Cheryl A.; Peters, C.J.; Ksiazek, Thomas G.; Li, Chung-Sheng; Patz, Jonathan A.; Mills, James N.

    2002-01-01

    The relationship between the risk of hantaviral pulmonary syndrome (HPS), as estimated from satellite imagery, and local rodent populations was examined. HPS risk, predicted before rodent sampling, was highly associated with the abundance of Peromyscus maniculatus, the reservoir of Sin Nombre virus (SNV). P. maniculatus were common in high-risk sites, and populations in high-risk areas were skewed toward adult males, the subclass most frequently infected with SNV. In the year after an El Niño Southern Oscillation (ENSO), captures of P. maniculatus increased only in high-risk areas. During 1998, few sites had infected mice, but by 1999, 18/20 of the high-risk sites contained infected mice and the crude prevalence was 30.8%. Only 1/18 of the low-risk sites contained infected rodents, and the prevalence of infection was lower (8.3%). Satellite imagery identified environmental features associated with SNV transmission within its reservoir population, but at least 2 years of high-risk conditions were needed for SNV to reach high prevalence. Areas with persistently high-risk environmental conditions may serve as refugia for the survival of SNV in local mouse populations.

  16. Novel Characteristics of Trypanosoma brucei Guanosine 5'-monophosphate Reductase Distinct from Host Animals

    PubMed Central

    Kimura, Chihiro; Shinohara, Takahiro; Tomiyama, Ai; Imamura, Akira; Kuwamura, Mitsuru; Nishimura, Kazuhiko; Fujimori, Ko; Shuto, Satoshi; Ishibashi, Osamu; Kubata, Bruno Kilunga; Inui, Takashi

    2016-01-01

    The metabolic pathway of purine nucleotides in parasitic protozoa is a potent drug target for treatment of parasitemia. Guanosine 5’-monophosphate reductase (GMPR), which catalyzes the deamination of guanosine 5’-monophosphate (GMP) to inosine 5’-monophosphate (IMP), plays an important role in the interconversion of purine nucleotides to maintain the intracellular balance of their concentration. However, only a few studies on protozoan GMPR have been reported at present. Herein, we identified the GMPR in Trypanosoma brucei, a causative protozoan parasite of African trypanosomiasis, and found that the GMPR proteins were consistently localized to glycosomes in T. brucei bloodstream forms. We characterized its recombinant protein to investigate the enzymatic differences between GMPRs of T. brucei and its host animals. T. brucei GMPR was distinct in having an insertion of a tandem repeat of the cystathionine β-synthase (CBS) domain, which was absent in mammalian and bacterial GMPRs. The recombinant protein of T. brucei GMPR catalyzed the conversion of GMP to IMP in the presence of NADPH, and showed apparent affinities for both GMP and NADPH different from those of its mammalian counterparts. Interestingly, the addition of monovalent cations such as K+ and NH4+ to the enzymatic reaction increased the GMPR activity of T. brucei, whereas none of the mammalian GMPR’s was affected by these cations. The monophosphate form of the purine nucleoside analog ribavirin inhibited T. brucei GMPR activity, though mammalian GMPRs showed no or only a little inhibition by it. These results suggest that the mechanism of the GMPR reaction in T. brucei is distinct from that in the host organisms. Finally, we demonstrated the inhibitory effect of ribavirin on the proliferation of trypanosomes in a dose-dependent manner, suggesting the availability of ribavirin to develop a new therapeutic agent against African trypanosomiasis. PMID:26731263

  17. The Modes of Evolutionary Emergence of Primal and Late Pandemic Influenza Virus Strains from Viral Reservoir in Animals: An Interdisciplinary Analysis

    PubMed Central

    Shoham, Dany

    2011-01-01

    Based on a wealth of recent findings, in conjunction with earliest chronologies pertaining to evolutionary emergences of ancestral RNA viruses, ducks, Influenzavirus A (assumingly within ducks), and hominids, as well as to the initial domestication of mallard duck (Anas platyrhynchos), jungle fowl (Gallus gallus), wild turkey (Meleagris gallopavo), wild boar (Sus scrofa), and wild horse (Equus ferus), presumed genesis modes of primordial pandemic influenza strains have multidisciplinarily been configured. The virological fundamentality of domestication and farming of those various avian and mammalian species has thereby been demonstrated and broadly elucidated, within distinctive coevolutionary paradigms. The mentioned viral genesis modes were then analyzed, compatibly with common denominators and flexibility that mark the geographic profile of the last 18 pandemic strains, which reputedly emerged since 1510, the antigenic profile of the last 10 pandemic strains since 1847, and the genomic profile of the last 5 pandemic strains since 1918, until present. Related ecophylogenetic and biogeographic aspects have been enlightened, alongside with the crucial role of spatial virus gene dissemination by avian hosts. A fairly coherent picture of primary and late evolutionary and genomic courses of pandemic strains has thus been attained, tentatively. Specific patterns underlying complexes prone to generate past and future pandemic strains from viral reservoir in animals are consequentially derived. PMID:23074663

  18. Strategies of exploitation of mammalian reservoirs by Bartonella species.

    PubMed

    Deng, Hongkuan; Le Rhun, Danielle; Buffet, Jean-Philippe R; Cotté, Violaine; Read, Amanda; Birtles, Richard J; Vayssier-Taussat, Muriel

    2012-02-27

    Numerous mammal species, including domestic and wild animals such as ruminants, dogs, cats and rodents, as well as humans, serve as reservoir hosts for various Bartonella species. Some of those species that exploit non-human mammals as reservoir hosts have zoonotic potential. Our understanding of interactions between bartonellae and reservoir hosts has been greatly improved by the development of animal models for infection and the use of molecular tools allowing large scale mutagenesis of Bartonella species. By reviewing and combining the results of these and other approaches we can obtain a comprehensive insight into the molecular interactions that underlie the exploitation of reservoir hosts by Bartonella species, particularly the well-studied interactions with vascular endothelial cells and erythrocytes.

  19. Strategies of exploitation of mammalian reservoirs by Bartonella species

    PubMed Central

    2012-01-01

    Numerous mammal species, including domestic and wild animals such as ruminants, dogs, cats and rodents, as well as humans, serve as reservoir hosts for various Bartonella species. Some of those species that exploit non-human mammals as reservoir hosts have zoonotic potential. Our understanding of interactions between bartonellae and reservoir hosts has been greatly improved by the development of animal models for infection and the use of molecular tools allowing large scale mutagenesis of Bartonella species. By reviewing and combining the results of these and other approaches we can obtain a comprehensive insight into the molecular interactions that underlie the exploitation of reservoir hosts by Bartonella species, particularly the well-studied interactions with vascular endothelial cells and erythrocytes. PMID:22369683

  20. Comparative Analysis of Transcriptional Profiles of Adult Schistosoma japonicum from Different Laboratory Animals and the Natural Host, Water Buffalo

    PubMed Central

    Wu, Chuang; Hou, Nan; Chen, Qijun

    2015-01-01

    Background Schistosomiasis is one of the most widely distributed parasitic diseases in the world. Schistosoma japonicum, a zoonotic parasite with a wide range of mammalian hosts, is one of the major pathogens of this disease. Although numerous studies on schistosomiasis japonica have been performed using laboratory animal models, systematic comparative analysis of whole-genome expression profiles in parasites from different laboratory animals and nature mammalian hosts is lacking to date. Methodology/Principal Findings Adult schistosomes were obtained from laboratory animals BALB/c mice, C57BL/6 mice, New Zealand white rabbits and the natural host, water buffaloes. The gene expression profiles of schistosomes from these animals were obtained and compared by genome-wide oligonucleotide microarray analysis. The results revealed that the gene expression profiles of schistosomes from different laboratory animals and buffaloes were highly consistent (r>0.98) genome-wide. Meanwhile, a total of 450 genes were identified to be differentially expressed in schistosomes which can be clustered into six groups. Pathway analysis revealed that these genes were mainly involved in multiple signal transduction pathways, amino acid, energy, nucleotide and lipid metabolism. We also identified a group of 1,540 abundantly and stably expressed gene products in adult worms, including a panel of 179 Schistosoma- or Platyhelminthes-specific genes that may be essential for parasitism and may be regarded as novel potential anti-parasite intervention targets for future research. Conclusions/Significance This study provides a comprehensive database of gene expression profiles of schistosomes derived from different laboratory animals and water buffaloes. An expanded number of genes potentially affecting the development of schistosomes in different animals were identified. These findings lay the foundation for schistosomiasis research in different laboratory animals and natural hosts at the

  1. Influence of laboratory animal hosts on the life cycle of Hyalomma marginatum and implications for an in vivo transmission model for Crimean-Congo hemorrhagic fever virus

    PubMed Central

    Gargili, Aysen; Thangamani, Saravanan; Bente, Dennis

    2013-01-01

    Crimean-Congo hemorrhagic fever virus (CCHFV) is one of the most geographically widespread arboviruses and causes a severe hemorrhagic syndrome in humans. The virus circulates in nature in a vertebrate-tick cycle and ticks of the genus Hyalomma are the main vectors and reservoirs. Although the tick vector plays a central role in the maintenance and transmission of CCHFV in nature, comparatively little is known of CCHFV-tick interactions. This is mostly due to the fact that establishing tick colonies is laborious, and working with CCHFV requires a biosafety level 4 laboratory (BSL4) in many countries. Nonetheless, an in vivo transmission model is essential to understand the epidemiology of the transmission cycle of CCHFV. In addition, important parameters such as vectorial capacity of tick species, levels of infection in the host necessary to infect the tick, and aspects of virus transmission by tick bite including the influence of tick saliva, cannot be investigated any other way. Here, we evaluate the influence of different laboratory animal species as hosts supporting the life cycle of Hyalomma marginatum, a two-host tick. Rabbits were considered the host of choice for the maintenance of the uninfected colonies due to high larval attachment rates, shorter larval-nymphal feeding times, higher nymphal molting rates, high egg hatching rates, and higher conversion efficiency index (CEI). Furthermore, we describe the successful establishment of an in vivo transmission model for CCHFV in a BSL4 biocontainment setting using interferon knockout mice. This will give us a new tool to study the transmission and interaction of CCHFV with its tick vector. PMID:23971007

  2. High Leptospira Diversity in Animals and Humans Complicates the Search for Common Reservoirs of Human Disease in Rural Ecuador

    PubMed Central

    Chiriboga, Jorge; Miller, Erin; Olivas, Sonora; Birdsell, Dawn; Hepp, Crystal; Hornstra, Heidie; Schupp, James M.; Morales, Melba; Gonzalez, Manuel; Reyes, Soraya; de la Cruz, Carmen; Keim, Paul; Hartskeerl, Rudy; Trueba, Gabriel; Pearson, Talima

    2016-01-01

    Background Leptospirosis is a zoonotic disease responsible for high morbidity around the world, especially in tropical and low income countries. Rats are thought to be the main vector of human leptospirosis in urban settings. However, differences between urban and low-income rural communities provide additional insights into the epidemiology of the disease. Methodology/Principal findings Our study was conducted in two low-income rural communities near the coast of Ecuador. We detected and characterized infectious leptospira DNA in a wide variety of samples using new real time quantitative PCR assays and amplicon sequencing. We detected infectious leptospira in a high percentage of febrile patients (14.7%). In contrast to previous studies on leptospirosis risk factors, higher positivity was not found in rats (3.0%) but rather in cows (35.8%) and pigs (21.1%). Six leptospira species were identified (L. borgpetersenii, L kirschnerii, L santarosai, L. interrogans, L noguchii, and an intermediate species within the L. licerasiae and L. wolffii clade) and no significant differences in the species of leptospira present in each animal species was detected (χ2 = 9.89, adj.p-value = 0.27). Conclusions/Significance A large portion of the world’s human population lives in low-income, rural communities, however, there is limited information about leptospirosis transmission dynamics in these settings. In these areas, exposure to peridomestic livestock is particularly common and high prevalence of infectious leptospira in cows and pigs suggest that they may be the most important reservoir for human transmission. Genotyping clinical samples show that multiple species of leptospira are involved in human disease. As these genotypes were also detected in samples from a variety of animals, genotype data must be used in conjunction with epidemiological data to provide evidence of transmission and the importance of different potential leptospirosis reservoirs. PMID:27622673

  3. What determines species richness of parasitic organisms? A meta-analysis across animal, plant and fungal hosts.

    PubMed

    Kamiya, Tsukushi; O'Dwyer, Katie; Nakagawa, Shinichi; Poulin, Robert

    2014-02-01

    Although a small set of external factors account for much of the spatial variation in plant and animal diversity, the search continues for general drivers of variation in parasite species richness among host species. Qualitative reviews of existing evidence suggest idiosyncrasies and inconsistent predictive power for all proposed determinants of parasite richness. Here, we provide the first quantitative synthesis of the evidence using a meta-analysis of 62 original studies testing the relationship between parasite richness across animal, plant and fungal hosts, and each of its four most widely used presumed predictors: host body size, host geographical range size, host population density, and latitude. We uncover three universal predictors of parasite richness across host species, namely host body size, geographical range size and population density, applicable regardless of the taxa considered and independently of most aspects of study design. A proper match in the primary studies between the focal predictor and both the spatial scale of study and the level at which parasite species richness was quantified (i.e. within host populations or tallied across a host species' entire range) also affected the magnitude of effect sizes. By contrast, except for a couple of indicative trends in subsets of the full dataset, there was no strong evidence for an effect of latitude on parasite species richness; where found, this effect ran counter to the general latitude gradient in diversity, with parasite species richness tending to be higher further from the equator. Finally, the meta-analysis also revealed a negative relationship between the magnitude of effect sizes and the year of publication of original studies (i.e. a time-lag bias). This temporal bias may be due to the increasing use of phylogenetic correction in comparative analyses of parasite richness over time, as this correction yields more conservative effect sizes. Overall, these findings point to common underlying

  4. Escherichia coli O157:H7: Animal Reservoir and Sources of Human Infection

    PubMed Central

    Ferens, Witold A.

    2011-01-01

    Abstract This review surveys the literature on carriage and transmission of enterohemorrhagic Escherichia coli (EHEC) O157:H7 in the context of virulence factors and sampling/culture technique. EHEC of the O157:H7 serotype are worldwide zoonotic pathogens responsible for the majority of severe cases of human EHEC disease. EHEC O157:H7 strains are carried primarily by healthy cattle and other ruminants, but most of the bovine strains are not transmitted to people, and do not exhibit virulence factors associated with human disease. Prevalence of EHEC O157:H7 is probably underestimated. Carriage of EHEC O157:H7 by individual animals is typically short-lived, but pen and farm prevalence of specific isolates may extend for months or years and some carriers, designated as supershedders, may harbor high intestinal numbers of the pathogen for extended periods. The prevalence of EHEC O157:H7 in cattle peaks in the summer and is higher in postweaned calves and heifers than in younger and older animals. Virulent strains of EHEC O157:H7 are rarely harbored by pigs or chickens, but are found in turkeys. The bacteria rarely occur in wildlife with the exception of deer and are only sporadically carried by domestic animals and synanthropic rodents and birds. EHEC O157:H7 occur in amphibian, fish, and invertebrate carriers, and can colonize plant surfaces and tissues via attachment mechanisms different from those mediating intestinal attachment. Strains of EHEC O157:H7 exhibit high genetic variability but typically a small number of genetic types predominate in groups of cattle and a farm environment. Transmission to people occurs primarily via ingestion of inadequately processed contaminated food or water and less frequently through contact with manure, animals, or infected people. PMID:21117940

  5. A Novel Extracellular Metallopeptidase Domain Shared by Animal Host-Associated Mutualistic and Pathogenic Microbes

    PubMed Central

    Nakjang, Sirintra; Ndeh, Didier A.; Wipat, Anil; Bolam, David N.; Hirt, Robert P.

    2012-01-01

    The mucosal microbiota is recognised as an important factor for our health, with many disease states linked to imbalances in the normal community structure. Hence, there is considerable interest in identifying the molecular basis of human-microbe interactions. In this work we investigated the capacity of microbes to thrive on mucosal surfaces, either as mutualists, commensals or pathogens, using comparative genomics to identify co-occurring molecular traits. We identified a novel domain we named M60-like/PF13402 (new Pfam entry PF13402), which was detected mainly among proteins from animal host mucosa-associated prokaryotic and eukaryotic microbes ranging from mutualists to pathogens. Lateral gene transfers between distantly related microbes explained their shared M60-like/PF13402 domain. The novel domain is characterised by a zinc-metallopeptidase-like motif and is distantly related to known viral enhancin zinc-metallopeptidases. Signal peptides and/or cell surface anchoring features were detected in most microbial M60-like/PF13402 domain-containing proteins, indicating that these proteins target an extracellular substrate. A significant subset of these putative peptidases was further characterised by the presence of associated domains belonging to carbohydrate-binding module family 5/12, 32 and 51 and other glycan-binding domains, suggesting that these novel proteases are targeted to complex glycoproteins such as mucins. An in vitro mucinase assay demonstrated degradation of mammalian mucins by a recombinant form of an M60-like/PF13402-containing protein from the gut mutualist Bacteroides thetaiotaomicron. This study reveals that M60-like domains are peptidases targeting host glycoproteins. These peptidases likely play an important role in successful colonisation of both vertebrate mucosal surfaces and the invertebrate digestive tract by both mutualistic and pathogenic microbes. Moreover, 141 entries across various peptidase families described in the MEROPS

  6. Phylogeographic Structure of the White-Footed Mouse and the Deer Mouse, Two Lyme Disease Reservoir Hosts in Québec.

    PubMed

    Fiset, Jessica; Tessier, Nathalie; Millien, Virginie; Lapointe, Francois-Joseph

    2015-01-01

    Modification of a species range is one of many consequences of climate change and is driving the emergence of Lyme disease in eastern Canada. The primary reservoir host of the bacteria responsible for Lyme disease, Borrelia burgdorferi, is the white-footed mouse (Peromyscus leucopus), whose range is rapidly shifting north into southern Québec. The deer mouse, P. maniculatus, is occurring over most Québec province and is a less competent host for B. burgdorferi. Here, we compared the phylogeographic structure of both Peromyscus species in Québec. Using a combination of multiple mitochondrial DNA markers and phylogeographic methods, we detected an ongoing and rapid expansion of P. leucopus, while P. maniculatus appears more stable. Haplotype and populations networks indicated that populations of P. maniculatus exhibit more genetic structure than P. leucopus across the study area. Furthermore, significant and consistent genetic divergences between populations of the two species on both sides of the St. Lawrence River suggest that distinct lineages of P. leucopus and P. maniculatus with different ancestral origins colonized Southern Québec following the Last Glacial Maximum. The phylogeographic structure of pathogens is expected to mirror the structure observed in their reservoir hosts. As different strains of Borrelia burgdorferi may be associated with different levels of pathogenicity and immune responses of their hosts, our results are helpful at better understanding the pattern of spread of Lyme disease in a zone of emergence, and associated risk for human populations.

  7. Phylogeographic Structure of the White-Footed Mouse and the Deer Mouse, Two Lyme Disease Reservoir Hosts in Québec

    PubMed Central

    Fiset, Jessica; Tessier, Nathalie; Millien, Virginie; Lapointe, Francois-Joseph

    2015-01-01

    Modification of a species range is one of many consequences of climate change and is driving the emergence of Lyme disease in eastern Canada. The primary reservoir host of the bacteria responsible for Lyme disease, Borrelia burgdorferi, is the white-footed mouse (Peromyscus leucopus), whose range is rapidly shifting north into southern Québec. The deer mouse, P. maniculatus, is occurring over most Québec province and is a less competent host for B. burgdorferi. Here, we compared the phylogeographic structure of both Peromyscus species in Québec. Using a combination of multiple mitochondrial DNA markers and phylogeographic methods, we detected an ongoing and rapid expansion of P. leucopus, while P. maniculatus appears more stable. Haplotype and populations networks indicated that populations of P. maniculatus exhibit more genetic structure than P. leucopus across the study area. Furthermore, significant and consistent genetic divergences between populations of the two species on both sides of the St. Lawrence River suggest that distinct lineages of P. leucopus and P. maniculatus with different ancestral origins colonized Southern Québec following the Last Glacial Maximum. The phylogeographic structure of pathogens is expected to mirror the structure observed in their reservoir hosts. As different strains of Borrelia burgdorferi may be associated with different levels of pathogenicity and immune responses of their hosts, our results are helpful at better understanding the pattern of spread of Lyme disease in a zone of emergence, and associated risk for human populations. PMID:26633555

  8. A STUDY OF THE SPECIFIC LOCATION OF LEPTOSPIRES WITH RESPECT TO VARIOUS TISSUE CELLS OF INFECTED ANIMAL HOSTS.

    DTIC Science & Technology

    The objectives of the research were as follows: (1) To determine the specific location of leptospires with respect to various tissue cells of the...infected animal host. (2) To study histologic variations at the cellular level as a result of leptospiral activity. (3) To determine final...disposition and significance of morphologically intact leptospires within vesicular structures of hepatic and renal cells and (4) To compare the 3341 and MLS

  9. The impact of multiple infections on wild animal hosts: a review

    PubMed Central

    Bordes, Frédéric; Morand, Serge

    2011-01-01

    Field parasitological studies consistently demonstrate the reality of polyparasitism in natural systems. However, only recently, studies from ecological and evolutionary fields have emphasised a broad spectrum of potential multiple infections-related impacts. The main goal of our review is to reunify the different approaches on the impacts of polyparasitism, not only from laboratory or human medical studies but also from field or theoretical studies. We put forward that ecological and epidemiological determinants to explain the level of polyparasitism, which regularly affects not only host body condition, survival or reproduction but also host metabolism, genetics or immune investment. Despite inherent limitations of all these studies, multiple infections should be considered more systematically in wildlife to better appreciate the importance of parasite diversity in wildlife, cumulative effects of parasitism on the ecology and evolution of their hosts. PMID:22957114

  10. Host-targeted approaches to managing animal health: old problems and new tools.

    PubMed

    Cook, M E; Bütz, D E; Yang, M; Sand, J M

    2016-07-01

    Our fellow medical and regulatory scientists question the animal producer's dependence on antibiotics and antimicrobial chemicals in the production of animal products. Retail distributors and consumers are putting even more pressure on the animal industry to find new ways to produce meat without antibiotics and chemicals. In addition, federal funding agencies are increasingly pressuring researchers to conduct science that has application. In the review that follows, we outline our approach to finding novel ways to improve animal performance and health. We use a strict set of guidelines in our applied research as follows: (1) Does the work have value to society? (2) Does our team have the skills to innovate in the field? (3) Is the product we produce commercially cost-effective? (4) Are there any reasons why the general consumer will reject the technology? (5) Is it safe for the animal, consumer, and the environment? Within this framework, we describe 4 areas of research that have produced useful products, areas that we hope other scientists will likewise explore and innovate such as (1) methods to detect infection in herds and flocks, (2) methods to control systemic and mucosal inflammation, (3) improvements to intestinal barrier function, and (4) methods to strategically potentiate immune defense. We recognize that others are working in these areas, using different strategies, but believe our examples will illustrate the vast opportunity for research and innovation in a world without antibiotics. Animal scientists have been given a new challenge that may help shape the future of both animal and human medicine.

  11. Weather, host and vector — their interplay in the spread of insect-borne animal virus diseases

    PubMed Central

    Sellers, R. F.

    1980-01-01

    The spread of insect-borne animal virus diseases is influenced by a number of factors. Hosts migrate, move or are conveyed over long distances: vectors are carried on the wind for varying distances in search of hosts and breeding sites; weather and climate affect hosts and vectors through temperature, moisture and wind. As parasites of host and vector, viruses are carried by animals, birds and insects, and their spread can be correlated with the migration of hosts and the carriage of vectors on winds associated with the movements of the Intertropical Convergence Zone (ITCZ) and warm winds to the north and south of the limits of the ITCZ. The virus is often transmitted from a local cycle to a migratory cycle and back again. Examples of insect-borne virus diseases and their spread are analysed. Japanese, Murray Valley, Western equine, Eastern equine and St Louis encephalitis represent viruses transmitted by mosquito—bird or pig cycles. The areas experiencing infection with these viruses can be divided into a number of zones: A, B, C, D, E and F. In zone A there is a continuous cycle of virus in host and vector throughout the year; in zone B, there is an upsurge in the cycle during the wet season, but the cycle continues during the dry season; there is movement of infected vectors between and within zones A and B on the ITCZ and the virus is introduced to zone C by infected vectors on warm winds; persistence may occur in zone C if conditions are right. In zone D, virus is introduced each year by infected vectors on warm winds and the arrival of the virus coincides with the presence of susceptible nestling birds and susceptible piglets. The disappearance of virus occurs at the time when migrating mosquitoes and birds are returning to warmer climates. The virus is introduced to zone E only on occasions every 5-10 years when conditions are suitable. Infected hosts introduced to zone F do not lead to circulation of virus, since the climate is unsuitable for vectors

  12. Weather, host and vector--their interplay in the spread of insect-borne animal virus diseases.

    PubMed

    Sellers, R F

    1980-08-01

    The spread of insect-borne animal virus diseases is influenced by a number of factors. Hosts migrate, move or are conveyed over long distances: vectors are carried on the wind for varying distances in search of hosts and breeding sites; weather and climate affect hosts and vectors through temperature, moisture and wind. As parasites of host and vector, viruses are carried by animals, birds and insects, and their spread can be correlated with the migration of hosts and the carriage of vectors on winds associated with the movements of the Intertropical Convergence Zone (ITCZ) and warm winds to the north and south of the limits of the ITCZ. The virus is often transmitted from a local cycle to a migratory cycle and back again.Examples of insect-borne virus diseases and their spread are analysed. Japanese, Murray Valley, Western equine, Eastern equine and St Louis encephalitis represent viruses transmitted by mosquito-bird or pig cycles.THE AREAS EXPERIENCING INFECTION WITH THESE VIRUSES CAN BE DIVIDED INTO A NUMBER OF ZONES: A, B, C, D, E and F. In zone A there is a continuous cycle of virus in host and vector throughout the year; in zone B, there is an upsurge in the cycle during the wet season, but the cycle continues during the dry season; there is movement of infected vectors between and within zones A and B on the ITCZ and the virus is introduced to zone C by infected vectors on warm winds; persistence may occur in zone C if conditions are right. In zone D, virus is introduced each year by infected vectors on warm winds and the arrival of the virus coincides with the presence of susceptible nestling birds and susceptible piglets. The disappearance of virus occurs at the time when migrating mosquitoes and birds are returning to warmer climates. The virus is introduced to zone E only on occasions every 5-10 years when conditions are suitable. Infected hosts introduced to zone F do not lead to circulation of virus, since the climate is unsuitable for vectors. Zones A

  13. The infrequency of transmission of herpesviruses between humans and animals; postulation of an unrecognised protective host mechanism.

    PubMed

    Skinner, G R; Ahmad, A; Davies, J A

    2001-10-01

    The infrequency of natural transmission of herpesviruses between humans and animals is surprising as there is extensive contact between humans and non-human species with unequivocal evidence that host cells from non-susceptible species will support replication of herpesviruses which do not seem to naturally infect that species. This review examines natural cross-infections between human and other species and suggests that, firstly, it is possible that humans and animals do become asymptomatically or symptomatically cross-infected from other species, but the infection is not diagnosed or not diagnosable by conventional methods; secondly, an as yet unidentified novel mechanism(s) may operate to prevent infection using chemical, electrical or as yet unidentified pathways and may even be 'switched on' by exposure to the virus.

  14. Role of Cannomys badius as a Natural Animal Host of Penicillium marneffei in India

    PubMed Central

    Gugnani, Harish; Fisher, Matthew C.; Paliwal-Johsi, Anubha; Vanittanakom, Nongnuch; Singh, Irabanta; Yadav, Pratap Singh

    2004-01-01

    Infection by Penicillium marneffei in human immunodeficiency virus-positive patients in India has recently been described; the aim of our study was to survey wild rodents and their associated environment in order to identify the natural populations of this fungus. Surveys recovered P. marneffei from the internal organs of 10 (9.1%) of 110 bamboo rats (Cannomys badius) examined from Manipur state, India, an area endemic for penicilliosis marneffei. Identification of the isolates was based on a detailed study of their morphological characteristics, in vitro conversion to fission yeast form, and exoantigen tests. Multilocus microsatellite typing (MLMT) of the isolates revealed five genotypes. No genotypes were shared between sample sites, and all bamboo rats were infected with a single genotype within sample sites, demonstrating spatial genetic heterogeneity. One MLMT genotype was identical to that seen in a human isolate, suggesting that either coinfection from a common source or host-to-host transmission had occurred. This demonstrates the utility of an MLMT-based approach to elucidating the epidemiology of P. marneffei. PMID:15528698

  15. Role of Cannomys badius as a natural animal host of Penicillium marneffei in India.

    PubMed

    Gugnani, Harish; Fisher, Matthew C; Paliwal-Johsi, Anubha; Vanittanakom, Nongnuch; Singh, Irabanta; Yadav, Pratap Singh

    2004-11-01

    Infection by Penicillium marneffei in human immunodeficiency virus-positive patients in India has recently been described; the aim of our study was to survey wild rodents and their associated environment in order to identify the natural populations of this fungus. Surveys recovered P. marneffei from the internal organs of 10 (9.1%) of 110 bamboo rats (Cannomys badius) examined from Manipur state, India, an area endemic for penicilliosis marneffei. Identification of the isolates was based on a detailed study of their morphological characteristics, in vitro conversion to fission yeast form, and exoantigen tests. Multilocus microsatellite typing (MLMT) of the isolates revealed five genotypes. No genotypes were shared between sample sites, and all bamboo rats were infected with a single genotype within sample sites, demonstrating spatial genetic heterogeneity. One MLMT genotype was identical to that seen in a human isolate, suggesting that either coinfection from a common source or host-to-host transmission had occurred. This demonstrates the utility of an MLMT-based approach to elucidating the epidemiology of P. marneffei.

  16. Tick-Borne Transmission of Two Genetically Distinct Anaplasma marginale Strains following Superinfection of the Mammalian Reservoir Host

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Strain superinfection affects the dynamics of epidemiological spread of pathogens through a host population. Superinfection has recently been shown to occur for genetically distinct strains of the tick-borne pathogen Anaplasma marginale that encode distinctly different surface protein variants. Supe...

  17. Geothermal Potential of the Cascade and Aleutian Arcs, with Ranking of Individual Volcanic Centers for their Potential to Host Electricity-Grade Reservoirs

    SciTech Connect

    Shevenell, Lisa; Coolbaugh, Mark; Hinz, Nick; Stelling, Pete; Melosh, Glenn; Cumming, William

    2015-10-16

    This project brings a global perspective to volcanic arc geothermal play fairway analysis by developing statistics for the occurrence of geothermal reservoirs and their geoscience context worldwide in order to rank U.S. prospects. The focus of the work was to develop play fairways for the Cascade and Aleutian arcs to rank the individual volcanic centers in these arcs by their potential to host electricity grade geothermal systems. The Fairway models were developed by describing key geologic factors expected to be indicative of productive geothermal systems in a global training set, which includes 74 volcanic centers world-wide with current power production. To our knowledge, this is the most robust geothermal benchmark training set for magmatic systems to date that will be made public.

  18. Investigation of Chagas disease in four periurban areas in northeastern Brazil: epidemiologic survey in man, vectors, non-human hosts and reservoirs.

    PubMed

    Lima, Marli M; Sarquis, Otília; de Oliveira, Tiago Guedes; Gomes, Taís F; Coutinho, Carolina; Daflon-Teixeira, Natália F; Toma, Helena K; Britto, Constança; Teixeira, Bernardo R; D'Andrea, Paulo S; Jansen, Ana M; Bóia, Marcio N; Carvalho-Costa, Filipe A

    2012-03-01

    Chagas disease was investigated in four periurban areas of Ceará state, northeastern Brazil, through serological, parasitological and molecular methods in humans, reservoirs and vectors. A cross-sectional survey revealed a seroprevalence rate of 1.2% (13/1076 residents, six also proving positive through PCR). Trypanosoma cruzi infection was not detected in children under 10 years old. Triatoma pseudomaculata prevailed in the peridomiciles: 63 specimens, 69% (34/49) infected with trypanosomatids. Rhodnius nasutus was captured in Copernicia prunifera palm trees (n=280; 25.0% infected with trypanosomatids) and inside dwellings (n=8, all uninfected). Trypanosoma cruzi seropositive reservoirs, represented by Didelphis albiventris (n=27), Rattus rattus (n=24), Thrichomys laurentius (n=2), Mus musculus (n=1) and Monodelphis domestica (n=1), were identified. Among domestic dogs (n=96) seroprevalence reached 21.9%. Miniexon multiplex PCR assays characterized TcI in triatomines. Both TcI and TcII were detected in wild mammal hosts. We conclude that Trypanosoma cruzi circulates within a domestic zoonotic cycle, requiring continuous surveillance. Insecticide application to domiciles does not appear to prevent continuous reintroduction of wild triatomine specimens, presenting a challenge to authorities involved in Chagas disease control.

  19. Infection levels of proteocephalidean cestodes in Cichla piquiti (Osteichthyes: Cichlidae) of the Volta Grande Reservoir, Minas Gerais, Brazil, relative to host body weight and gender.

    PubMed

    Martins, M L; Pereira, J; de Chambrier, A; Mouriño, J L P

    2011-12-01

    We evaluated the relationship between infection by proteocephalid cestodes and the sex and weight classes of tucunaré (Cichla piquiti) captured between August 1999 and June 2001 in the Volta Grande Reservoir, Minas Gerais, Brazil. A total of 96 fish, 75.9 ± 9.3% males and 88.9 ± 6.4% females, were parasitized by Proteocephalus macrophallus and P. microscopicus, with total mean intensities of 76.6 ± 23.9 and 145.2 ± 36.7, respectively, during this period. In the majority of the months analysed, males showed 71.4-100% prevalence of parasitism and females 80-100%. Although there was no significant difference, females showed a higher mean intensity of infection (145.2 ± 36.7) than males (76.6 ± 23.9). Fish weighing 300-800 g showed a higher mean abundance of parasites (P < 0.05) compared with the biggest specimens weighing 801-2750 g. Analysing both males and females together, the greatest mean intensities of infection were found in October and December (P < 0.05) independent of the year, which coincides with the months of highest rainfall. These results show that fish living in reservoirs may be more susceptible to intermediate hosts than those that live in rivers.

  20. Inverse modelling of the reversely magnetized, shallow plumbing system hosting oil reservoirs of the Auca Mahuida volcano (Payeina retroarc, Neuquén Basin, Argentina)

    NASA Astrophysics Data System (ADS)

    Paine, John; De Ritis, Riccardo; Ventura, Guido; Longo, Mariana; Ravat, Dhananjay; Speranza, Fabio; Chiappini, Massimo

    2016-02-01

    The Auca Mahuida volcano (2.03-0.88 Ma) located east of the Andean thrust front in the Neuquén basin (Argentina) hosts an oil system of thermogenic origin and is affected by the NW-SE striking-faults. Intrusive bodies and the underlying Jurassic sediments constitute the reservoir rocks. Aeromagnetic data collected in the Auca Mahuida area detected multiple dipolar magnetic anomalies, many of which have reverse polarity. Palaeomagnetic measurements on rock samples collected in the field together with available age determinations indicate that the reversely magnetized sources were mainly emplaced during the Matuyama reverse polarity chron while the normal polarity sources were emplaced during the Olduvai and/or Jaramillo subchrons. The location and geometry of the intrusive bodies is poorly known and the customary magnetic inversion is rendered difficult because of multiple natural remanent magnetization directions. To address these difficulties, a voxel inversion was applied to model the vector residual magnetic intensity (VRMI) transformation of the observed total magnetic intensity data. The modelling showed a 1.5 km deep, subcircular ring-shaped intrusion below the summit of the volcano and a series of NW-SE elongated, fault-controlled intrusive bodies to depths up to 3-4 km. Our results show that magnetic data and VRMI modelling help resolve the geometry of the shallow plumbing system of volcanoes with remanently magnetized sources, and estimate the depth and geometry of potential oil reservoirs in volcanic areas.

  1. The evolutionary history of symbiotic associations among bacteria and their animal hosts: a model.

    PubMed

    Moya, A; Gil, R; Latorre, A

    2009-01-01

    A model to explain the evolutionary history of animal-bacteria obligatory mutualistic symbiosis is presented. Dispensability of genes and genetic isolation are key factors in the reduction process of these bacterial genomes. Major steps in such genome reductive evolution, leading towards primary endosimbiosis, and the possibility of complementation or replacement by a secondary symbiont are also indicated. Yet, we need to understand what happens at the beginning of the adaptative process towards an obligate mutualistic relationship. For this purpose, we propose to sequence the complete genome of SOPE, the primary endosymbiont of the rice weevil.

  2. How temperature-dependent elasticity alters host rock/magmatic reservoir models: A case study on the effects of ice-cap unloading on shallow volcanic systems

    NASA Astrophysics Data System (ADS)

    Bakker, Richard R.; Frehner, Marcel; Lupi, Matteo

    2016-12-01

    In geodynamic numerical models of volcanic systems, the volcanic basement hosting the magmatic reservoir is often assumed to exhibit constant elastic parameters with a sharp transition from the host rocks to the magmatic reservoir. We assess this assumption by deriving an empirical relation between elastic parameters and temperature for Icelandic basalts by conducting a set of triaxial compression experiments between 200 °C and 1000 °C. Results show a significant decrease of Young's modulus from ∼38 GPa to less than 4.7 GPa at around 1000 °C. Based on these laboratory data, we develop a 2D axisymmetric finite-element model including temperature-dependent elastic properties of the volcanic basement. As a case study, we use the Snæfellsjökull volcanic system, Western Iceland to evaluate pressure differences in the volcanic edifice and basement due to glacial unloading of the volcano. First, we calculate the temperature field throughout the model and assign elastic properties accordingly. Then we assess unloading-driven pressure differences in the magma chamber at various depths in models with and without temperature-dependent elastic parameters. With constant elastic parameters and a sharp transition between basement and magma chamber we obtain results comparable to other studies. However, pressure changes due to surface unloading become smaller when using more realistic temperature-dependent elastic properties. We ascribe this subdued effect to a transition zone around the magma chamber, which is still solid rock but with relatively low Young's modulus due to high temperatures. We discuss our findings in the light of volcanic processes in proximity to the magma chamber, such as roof collapse, dyke injection, or deep hydrothermal circulation. Our results aim at quantifying the effects of glacial unloading on magma chamber dynamics and volcanic activity.

  3. Experimental infection studies demonstrating Atlantic salmon as a host and reservoir of viral hemorrhagic septicemia virus type IVa with insights into pathology and host immunity.

    PubMed

    Lovy, J; Piesik, P; Hershberger, P K; Garver, K A

    2013-09-27

    In British Columbia, Canada (BC), aquaculture of finfish in ocean netpens has the potential for pathogen transmission between wild and farmed species due to the sharing of an aquatic environment. Viral hemorrhagic septicemia virus (VHSV) is enzootic in BC and causes serious disease in wild Pacific herring, Clupea pallasii, which often enter and remain in Atlantic salmon, Salmo salar, netpens. Isolation of VHSV from farmed Atlantic salmon has been previously documented, but the effects on the health of farmed salmon and the wild fish sharing the environment are unknown. To determine their susceptibility, Atlantic salmon were exposed to a pool of 9 isolates of VHSV obtained from farmed Atlantic salmon in BC by IP-injection or by waterborne exposure and cohabitation with diseased Pacific herring. Disease intensity was quantified by recording mortality, clinical signs, histopathological changes, cellular sites of viral replication, expression of interferon-related genes, and viral tissue titers. Disease ensued in Atlantic salmon after both VHSV exposure methods. Fish demonstrated gross disease signs including darkening of the dorsal skin, bilateral exophthalmia, light cutaneous hemorrhage, and lethargy. The virus replicated within endothelial cells causing endothelial cell necrosis and extensive hemorrhage in anterior kidney. Infected fish demonstrated a type I interferon response as seen by up-regulation of genes for IFNα, Mx, and ISG15. In a separate trial infected salmon transmitted the virus to sympatric Pacific herring. The results demonstrate that farmed Atlantic salmon can develop clinical VHS and virus can persist in the tissues for at least 10 weeks. Avoiding VHS epizootics in Atlantic salmon farms would limit the potential of VHS in farmed Atlantic salmon, the possibility for further host adaptation in this species, and virus spillback to sympatric wild fishes.

  4. Experimental infection studies demonstrating Atlantic salmon as a host and reservoir of viral hemorrhagic septicemia virus type IVa with insights into pathology and host immunity

    USGS Publications Warehouse

    Lovy, Jan; Piesik, P.; Hershberger, P.K.; Garver, K.A.

    2013-01-01

    In British Columbia, Canada (BC), aquaculture of finfish in ocean netpens has the potential for pathogen transmission between wild and farmed species due to the sharing of an aquatic environment. Viral hemorrhagic septicemia virus (VHSV) is enzootic in BC and causes serious disease in wild Pacific herring, Clupea pallasii, which often enter and remain in Atlantic salmon, Salmo salar, netpens. Isolation of VHSV from farmed Atlantic salmon has been previously documented, but the effects on the health of farmed salmon and the wild fish sharing the environment are unknown. To determine their susceptibility, Atlantic salmon were exposed to a pool of 9 isolates of VHSV obtained from farmed Atlantic salmon in BC by IP-injection or by waterborne exposure and cohabitation with diseased Pacific herring. Disease intensity was quantified by recording mortality, clinical signs, histopathological changes, cellular sites of viral replication, expression of interferon-related genes, and viral tissue titers. Disease ensued in Atlantic salmon after both VHSV exposure methods. Fish demonstrated gross disease signs including darkening of the dorsal skin, bilateral exophthalmia, light cutaneous hemorrhage, and lethargy. The virus replicated within endothelial cells causing endothelial cell necrosis and extensive hemorrhage in anterior kidney. Infected fish demonstrated a type I interferon response as seen by up-regulation of genes for IFNα, Mx, and ISG15. In a separate trial infected salmon transmitted the virus to sympatric Pacific herring. The results demonstrate that farmed Atlantic salmon can develop clinical VHS and virus can persist in the tissues for at least 10 weeks. Avoiding VHS epizootics in Atlantic salmon farms would limit the potential of VHS in farmed Atlantic salmon, the possibility for further host adaptation in this species, and virus spillback to sympatric wild fishes.

  5. Animator

    ERIC Educational Resources Information Center

    Tech Directions, 2008

    2008-01-01

    Art and animation work is the most significant part of electronic game development, but is also found in television commercials, computer programs, the Internet, comic books, and in just about every visual media imaginable. It is the part of the project that makes an abstract design idea concrete and visible. Animators create the motion of life in…

  6. Studies on rodents role as reservoir hosts of leishmaniasis with specical reference to their ectoparasites in Suez Governorate.

    PubMed

    Shoukry, Nahla M; El-Naggar, Mostafa H; Darwish, Ahmed B; Soliman, Belal A; El-Sawaf, Bahira M

    2006-04-01

    The distribution of rodents was studied in three different habitats. Seven rodent species were identified: Rattus norvegicus, R. alexandrinus, R. frugivorous, Mus musculus, Acomys russatus, Meriones sacramenti and Gerbillus pyramidum. The species distribution varied with the habitat type. The highest density of rodents was in July and August and the lowest one was in January. However, some species were collected all the year round. The rodents were investigated for the endo- and ecto-parasites. No Leishmania parasites were found. The ectoparasites were: Xenopsylla cheopis, Leptopsylla segnis and Ctenocephalides felis, Polyplax spinulos, Hyalomma dromedarii (nymph) and Echinolaelaps echidninus and Hemolaelaps glassgowi. Ecto-parasites were on rodents all year-round in domestic habitat and peridomestic habitats. In wild one, ecto-parasites activity was from March to December. The rodents' role as reservoir for L. major was experimentally studied. Rodents inoculated with L. major together with hamster and BALB-c mice developed cutaneous lesions. The active lesions, the rodents' ecological habitats and the presence of insect-vector may pave the way to an epidemic zoonotic leishmaniasis role.

  7. Detection of Leptospira spp. in wildlife reservoir hosts in Ontario through comparison of immunohistochemical and polymerase chain reaction genotyping methods

    PubMed Central

    Shearer, Karen E.; Harte, Michael J.; Ojkic, Davor; DeLay, Josepha; Campbell, Douglas

    2014-01-01

    A total of 460 kidney samples from wildlife (beavers, coyotes, deer, foxes, opossums, otters, raccoons, skunks) were obtained from road-kill and hunter/trapper donations in Ontario between January 2010 and November 2012. The objectives of the study were to detect Leptospira spp. by immunohistochemistry and polymerase chain reaction (PCR), to map presence of leptospires in wildlife relative to livestock and human populations, and to characterize positive samples by sequencing and comparison to leptospires known to affect domestic animals and humans. The proportion of samples that tested positive ranged from 0% to 42%, with the highest rates in skunks and raccoons. Leptospira spp. were present in kidneys of wildlife across Ontario, particularly in areas of high human density, and areas in which livestock populations are abundant. The PCR was too weak in most samples to permit genotyping and examination of the relationship between the leptospires found in this study and those affecting domestic animals and humans. PMID:24587507

  8. Insights into host-pathogen interactions from state-of-the-art animal models of respiratory Pseudomonas aeruginosa infections.

    PubMed

    Lorenz, Anne; Pawar, Vinay; Häussler, Susanne; Weiss, Siegfried

    2016-11-01

    Pseudomonas aeruginosa is an important opportunistic pathogen that can cause acute respiratory infections in immunocompetent patients or chronic infections in immunocompromised individuals and in patients with cystic fibrosis. When acquiring the chronic infection state, bacteria are encapsulated within biofilm structures enabling them to withstand diverse environmental assaults, including immune reactions and antimicrobial therapy. Understanding the molecular interactions within the bacteria, as well as with the host or other bacteria, is essential for developing innovative treatment strategies. Such knowledge might be accumulated in vitro. However, it is ultimately necessary to confirm these findings in vivo. In the present Review, we describe state-of-the-art in vivo models that allow studying P. aeruginosa infections in molecular detail. The portrayed mammalian models exclusively focus on respiratory infections. The data obtained by alternative animal models which lack lung tissue, often provide molecular insights that are easily transferable to mammals. Importantly, these surrogate in vivo systems reveal complex molecular interactions of P. aeruginosa with the host. Herein, we also provide a critical assessment of the advantages and disadvantages of such models.

  9. Viruses within animal genomes.

    PubMed

    De Brognier, A; Willems, L

    2016-04-01

    Viruses and their hosts can co-evolve to reach a fragile equilibrium that allows the survival of both. An excess of pathogenicity in the absence of a reservoir would be detrimental to virus survival. A significant proportion of all animal genomes has been shaped by the insertion of viruses that subsequently became 'fossilised'. Most endogenous viruses have lost the capacity to replicate via an infectious cycle and now replicate passively. The insertion of endogenous viruses has contributed to the evolution of animal genomes, for example in the reproductive biology of mammals. However, spontaneous viral integration still occasionally occurs in a number of virus-host systems. This constitutes a potential risk to host survival but also provides an opportunity for diversification and evolution.

  10. Climate-Driven Variation in the Intensity of a Host-Symbiont Animal Interaction along a Broad Elevation Gradient

    PubMed Central

    Meléndez, Leandro; Laiolo, Paola; Mironov, Sergey; García, Mónica; Magaña, Oscar; Jovani, Roger

    2014-01-01

    Gradients of environmental stress may affect biotic interactions in unpredictable ways responding to climate variation, depending on the abiotic stress tolerance of interacting partners. Here, we study the effect of local climate on the intensity of feather mites in six mountain passerines along a 1400 m elevational gradient characterized by shifting temperature and rainfall. Although obligatory symbionts of warm-blooded organisms are assumed to live in mild and homeothermic environments, those inhabiting external, non-blood-irrigated body portions of the host organism, such as feather mites, are expected to endure exposure to the direct influence of a fluctuating climate. As expected, feather mite intensity declined with elevation in all bird species, a pattern that was also found in cold-adapted passerines that have typical alpine habits. The elevation cline was mainly explained by a positive effect of the average temperature upon mite intensity in five of the six species studied. Precipitation explained less variance in mite intensity than average temperature, and showed a negative correlation in half of the studied species. We found no climate-driven migration of mites along the wings of birds, no replacement of mite species along elevation gradients and no association with available food resources for mites (estimated by the size of the uropygial gland). This study suggests that ectosymbionts of warm-blooded animals may be highly sensitive to climatic variation and become less abundant under stressful environmental conditions, providing empirical evidence of the decline of specialized biotic interactions among animal species at high elevations. PMID:25025873

  11. Domestic Animal Hosts Strongly Influence Human-Feeding Rates of the Chagas Disease Vector Triatoma infestans in Argentina

    PubMed Central

    Gürtler, Ricardo E.; Cecere, María C.; Vázquez-Prokopec, Gonzalo M.; Ceballos, Leonardo A.; Gurevitz, Juan M.; Fernández, María del Pilar; Kitron, Uriel; Cohen, Joel E.

    2014-01-01

    . Domestic animals in domiciles profoundly affect the host-feeding choices, human-vector contact rates and parasite transmission predicted by a model based on these estimates. PMID:24852606

  12. A Newly Emerged Cutaneous Leishmaniasis Focus in Northern Israel and Two New Reservoir Hosts of Leishmania major

    PubMed Central

    Faiman, Roy; Abbasi, Ibrahim; Jaffe, Charles; Motro, Yoav; Nasereddin, Abdelmagid; Schnur, Lionel F.; Torem, Moshe; Pratlong, Francine; Dedet, Jean-Pierre; Warburg, Alon

    2013-01-01

    In 2006/7, 18 cases of cutaneous leishmaniasis (CL) were reported for the first time from Sde Eliyahu (pop. 650), a village in the Beit She'an valley of Israel. Between 2007–2011, a further 88 CL cases were diagnosed bringing the total to 106 (16.3% of the population of Sde Eliyahu). The majority of cases resided in the south-western part of the village along the perimeter fence. The causative parasite was identified as Leishmania major Yakimoff & Schokhor, 1914 (Kinetoplastida: Trypanosomatidae). Phlebotomus papatasi (Scopoli), 1786 (Diptera: Psychodidae) was found to be the most abundant phlebotomine species comprising 97% of the sand flies trapped inside the village, and an average of 7.9% of the females were positive for Leishmania ITS1 DNA. Parasite isolates from CL cases and a sand fly were characterized using several methods and shown to be L. major. During a comprehensive survey of rodents 164 Levant voles Microtus guentheri Danford & Alston, 1880 (Rodentia: Cricetidae) were captured in alfalfa fields bordering the village. Of these 27 (16.5%) tested positive for Leishmania ITS1 DNA and shown to be L. major by reverse line blotting. A very high percentage (58.3% - 21/36) of Tristram's jirds Meriones tristrami Thomas, 1892 (Rodentia: Muridae), found further away from the village also tested positive for ITS1 by PCR. Isolates of L. major were successfully cultured from the ear of a wild jird found positive by ITS1 PCR. Although none of the wild PCR-positive voles exhibited external pathology, laboratory-reared voles that were infected by intradermal L. major inoculation, developed patent lesions and sand flies became infected by feeding on the ears of these laboratory-infected voles. This is the first report implicating M. guentheri and M. tristrami as reservoirs of Leishmania. The widespread co-distribution of M. guentheri and P. papatasi, suggests a significant threat from the spread of CL caused by L. major in the Middle East, central Asia and southern

  13. Differential cell line susceptibility to the emerging Zika virus: implications for disease pathogenesis, non-vector-borne human transmission and animal reservoirs

    PubMed Central

    Chan, Jasper Fuk-Woo; Yip, Cyril Chik-Yan; Tsang, Jessica Oi-Ling; Tee, Kah-Meng; Cai, Jian-Piao; Chik, Kenn Ka-Heng; Zhu, Zheng; Chan, Chris Chung-Sing; Choi, Garnet Kwan-Yue; Sridhar, Siddharth; Zhang, Anna Jinxia; Lu, Gang; Chiu, Kin; Lo, Amy Cheuk-Yin; Tsao, Sai-Wah; Kok, Kin-Hang; Jin, Dong-Yan; Chan, Kwok-Hung; Yuen, Kwok-Yung

    2016-01-01

    Zika virus (ZIKV) is unique among human-pathogenic flaviviruses by its association with congenital anomalies and trans-placental and sexual human-to-human transmission. Although the pathogenesis of ZIKV-associated neurological complications has been reported in recent studies, key questions on the pathogenesis of the other clinical manifestations, non-vector-borne transmission and potential animal reservoirs of ZIKV remain unanswered. We systematically characterized the differential cell line susceptibility of 18 human and 15 nonhuman cell lines to two ZIKV isolates (human and primate) and dengue virus type 2 (DENV-2). Productive ZIKV replication (⩾2 log increase in viral load, ZIKV nonstructural protein-1 (NS1) protein expression and cytopathic effects (CPE)) was found in the placental (JEG-3), neuronal (SF268), muscle (RD), retinal (ARPE19), pulmonary (Hep-2 and HFL), colonic (Caco-2),and hepatic (Huh-7) cell lines. These findings helped to explain the trans-placental transmission and other clinical manifestations of ZIKV. Notably, the prostatic (LNCaP), testicular (833KE) and renal (HEK) cell lines showed increased ZIKV load and/or NS1 protein expression without inducing CPE, suggesting their potential roles in sexual transmission with persistent viral replication at these anatomical sites. Comparatively, none of the placental and genital tract cell lines allowed efficient DENV-2 replication. Among the nonhuman cell lines, nonhuman primate (Vero and LLC-MK2), pig (PK-15), rabbit (RK-13), hamster (BHK21) and chicken (DF-1) cell lines supported productive ZIKV replication. These animal species may be important reservoirs and/or potential animal models for ZIKV. The findings in our study help to explain the viral shedding pattern, transmission and pathogenesis of the rapidly disseminating ZIKV, and are useful for optimizing laboratory diagnostics and studies on the pathogenesis and counter-measures of ZIKV. PMID:27553173

  14. Differential cell line susceptibility to the emerging Zika virus: implications for disease pathogenesis, non-vector-borne human transmission and animal reservoirs.

    PubMed

    Chan, Jasper Fuk-Woo; Yip, Cyril Chik-Yan; Tsang, Jessica Oi-Ling; Tee, Kah-Meng; Cai, Jian-Piao; Chik, Kenn Ka-Heng; Zhu, Zheng; Chan, Chris Chung-Sing; Choi, Garnet Kwan-Yue; Sridhar, Siddharth; Zhang, Anna Jinxia; Lu, Gang; Chiu, Kin; Lo, Amy Cheuk-Yin; Tsao, Sai-Wah; Kok, Kin-Hang; Jin, Dong-Yan; Chan, Kwok-Hung; Yuen, Kwok-Yung

    2016-08-24

    Zika virus (ZIKV) is unique among human-pathogenic flaviviruses by its association with congenital anomalies and trans-placental and sexual human-to-human transmission. Although the pathogenesis of ZIKV-associated neurological complications has been reported in recent studies, key questions on the pathogenesis of the other clinical manifestations, non-vector-borne transmission and potential animal reservoirs of ZIKV remain unanswered. We systematically characterized the differential cell line susceptibility of 18 human and 15 nonhuman cell lines to two ZIKV isolates (human and primate) and dengue virus type 2 (DENV-2). Productive ZIKV replication (⩾2 log increase in viral load, ZIKV nonstructural protein-1 (NS1) protein expression and cytopathic effects (CPE)) was found in the placental (JEG-3), neuronal (SF268), muscle (RD), retinal (ARPE19), pulmonary (Hep-2 and HFL), colonic (Caco-2),and hepatic (Huh-7) cell lines. These findings helped to explain the trans-placental transmission and other clinical manifestations of ZIKV. Notably, the prostatic (LNCaP), testicular (833KE) and renal (HEK) cell lines showed increased ZIKV load and/or NS1 protein expression without inducing CPE, suggesting their potential roles in sexual transmission with persistent viral replication at these anatomical sites. Comparatively, none of the placental and genital tract cell lines allowed efficient DENV-2 replication. Among the nonhuman cell lines, nonhuman primate (Vero and LLC-MK2), pig (PK-15), rabbit (RK-13), hamster (BHK21) and chicken (DF-1) cell lines supported productive ZIKV replication. These animal species may be important reservoirs and/or potential animal models for ZIKV. The findings in our study help to explain the viral shedding pattern, transmission and pathogenesis of the rapidly disseminating ZIKV, and are useful for optimizing laboratory diagnostics and studies on the pathogenesis and counter-measures of ZIKV.

  15. Microclimate impacts survival and prevalence of Phytophthora ramorum in Umbellularia californica, a key reservoir host of sudden oak death in Northern California forests.

    PubMed

    DiLeo, Matthew V; Bostock, Richard M; Rizzo, David M

    2014-01-01

    Phytophthora ramorum, an invasive pathogen and the causal agent of Sudden Oak Death, has become established in mixed-evergreen and redwood forests in coastal northern California. While oak and tanoak mortality is the most visible indication of P. ramorum's presence, epidemics are largely driven by the presence of bay laurel (Umbellularia californica), a reservoir host that supports both prolific sporulation in the winter wet season and survival during the summer dry season. In order to better understand how over-summer survival of the pathogen contributes to variability in the severity of annual epidemics, we monitored the viability of P. ramorum leaf infections over three years along with coincident microclimate. The proportion of symptomatic bay laurel leaves that contained viable infections decreased during the first summer dry season and remained low for the following two years, likely due to the absence of conducive wet season weather during the study period. Over-summer survival of P. ramorum was positively correlated with high percent canopy cover, less negative bay leaf water potential and few days exceeding 30°C but was not significantly different between mixed-evergreen and redwood forest ecosystems. Decreased summer survival of P. ramorum in exposed locations and during unusually hot summers likely contributes to the observed spatiotemporal heterogeneity of P. ramorum epidemics.

  16. Microclimate Impacts Survival and Prevalence of Phytophthora ramorum in Umbellularia californica, a Key Reservoir Host of Sudden Oak Death in Northern California Forests

    PubMed Central

    DiLeo, Matthew V.; Bostock, Richard M.; Rizzo, David M.

    2014-01-01

    Phytophthora ramorum, an invasive pathogen and the causal agent of Sudden Oak Death, has become established in mixed-evergreen and redwood forests in coastal northern California. While oak and tanoak mortality is the most visible indication of P. ramorum’s presence, epidemics are largely driven by the presence of bay laurel (Umbellularia californica), a reservoir host that supports both prolific sporulation in the winter wet season and survival during the summer dry season. In order to better understand how over-summer survival of the pathogen contributes to variability in the severity of annual epidemics, we monitored the viability of P. ramorum leaf infections over three years along with coincident microclimate. The proportion of symptomatic bay laurel leaves that contained viable infections decreased during the first summer dry season and remained low for the following two years, likely due to the absence of conducive wet season weather during the study period. Over-summer survival of P. ramorum was positively correlated with high percent canopy cover, less negative bay leaf water potential and few days exceeding 30°C but was not significantly different between mixed-evergreen and redwood forest ecosystems. Decreased summer survival of P. ramorum in exposed locations and during unusually hot summers likely contributes to the observed spatiotemporal heterogeneity of P. ramorum epidemics. PMID:25098281

  17. The effect of seasonality, density and climate on the population dynamics of Montana deer mice, important reservoir hosts for Sin Nombre hantavirus.

    PubMed

    Luis, Angela D; Douglass, Richard J; Mills, James N; Bjørnstad, Ottar N

    2010-03-01

    1. Since Sin Nombre virus was discovered in the U.S. in 1993, longitudinal studies of the rodent reservoir host, the deer mouse (Peromyscus maniculatus) have demonstrated a qualitative correlation among mouse population dynamics and risk of hantavirus pulmonary syndrome (HPS) in humans, indicating the importance of understanding deer mouse population dynamics for evaluating risk of HPS. 2. Using capture-mark-recapture statistical methods on a 15-year data set from Montana, we estimated deer mouse survival, maturation and recruitment rates and tested the relative importance of seasonality, population density and local climate in explaining temporal variation in deer mouse demography. 3. From these estimates, we designed a population model to simulate deer mouse population dynamics given climatic variables and compared the model to observed patterns. 4. Month, precipitation 5 months previously, temperature 5 months previously and to a lesser extent precipitation and temperature in the current month, were important in determining deer mouse survival. Month, the sum of precipitation over the last 4 months, and the sum of the temperature over the last 4 months were important in determining recruitment rates. Survival was more important in determining the growth rate of the population than recruitment. 5. While climatic drivers appear to have a complex influence on dynamics, our forecasts were good. Our quantitative model may allow public health officials to better predict increased human risk from basic climatic data.

  18. Sweet pepper confirmed as a reservoir host for tomato yellow leaf curl virus by both agro-inoculation and whitefly-mediated inoculation.

    PubMed

    Kil, Eui-Joon; Byun, Hee-Seong; Kim, Sunhoo; Kim, Jaedeok; Park, Jungan; Cho, Seungchan; Yang, Dong-Cheol; Lee, Kyeong-Yeoll; Choi, Hong-Soo; Kim, Ji-Kwang; Lee, Sukchan

    2014-09-01

    Tomato yellow leaf curl virus (TYLCV), a member of the genus Begomovirus, has a single-stranded DNA genome. TYLCV can induce severe disease symptoms on tomato plants, but other hosts plants such as cucurbits and peppers are asymptomatic. A full-length DNA clone of a Korean TYLCV isolate was constructed by rolling-circle amplification from TYLCV-infected tomatoes in Korea. To assess relative susceptibility of sweet pepper varieties to TYLCV, 19 cultivars were inoculated with cloned TYLCV by agro-inoculation. All TYLCV-infected sweet peppers were asymptomatic, even though Southern hybridization and polymerase chain reaction analysis showed TYLCV genomic DNA accumulation in roots, stems, and newly produced shoots. Southern hybridization indicated that TYLCV replicated and moved systemically from agro-inoculated apical shoot tips to roots or newly produced shoots of sweet peppers. Whitefly-mediated inoculation experiments showed that TYLCV can be transmitted to tomatoes from TYLCV-infected sweet peppers. Taken together, these results indicate that sweet pepper can be a reservoir for TYLCV in nature.

  19. Host-feeding patterns of Aedes albopictus (Diptera: Culicidae) in relation to availability of human and domestic animals in suburban landscapes of central North Carolina.

    PubMed

    Richards, Stephanie L; Ponnusamy, Loganathan; Unnasch, Thomas R; Hassan, Hassan K; Apperson, Charles S

    2006-05-01

    Aedes albopictus (Skuse) (Diptera: Culicidae) is a major nuisance mosquito and a potential arbovirus vector. The host-feeding patterns of Ae. albopictus were investigated during the 2002 and 2003 mosquito seasons in suburban neighborhoods in Wake County, Raleigh, NC. Hosts of blood-fed Ae. albopictus (n = 1,094) were identified with an indirect enzyme-linked immunosorbent assay, by using antisera made in New Zealand White rabbits to the sera of animals that would commonly occur in peridomestic habitats. Ae. albopictus fed predominantly on mammalian hosts (83%). Common mammalian hosts included humans (24%), cats (21%), and dogs (14%). However, a notable proportion (7%) of bloodmeals also was taken from avian hosts. Some bloodmeals taken from birds were identified to species by a polymerase chain reaction-heteroduplex assay (PCR-HDA). Ae. albopictus fed predominantly on chickens and a northern cardinal. PCR-HDA failed to produce detectable products for 29 (58%) of 50 bloodmeals for which DNA had been amplified, indicating that these mosquitoes took mixed bloodmeals from avian and nonavian hosts. Ae. albopictus preference for humans, dogs, and cats was determined by calculating host-feeding indices for the three host pairs based on the proportion of host specific blood-fed mosquitoes collected in relation to the number of specific hosts per residence as established by a door-to-door survey conducted in 2003. Estimates of the average amount of time that residents and their pets (cats and dogs) spent out of doors were obtained. Host-feeding indices based only on host abundance indicated that Ae. albopictus was more likely to feed on domestic animals. However, when feeding indices were time-weighted, Ae. albopictus fed preferentially upon humans. Ae. albopictus blood feeding on humans was investigated using a STR/PCR-DNA profiling technique that involved amplification of three short tandem repeats loci. Of 40 human bloodmeals, 32 (80%) were from a single human, whereas

  20. Rickettsial Infections among Ctenocephalides felis and Host Animals during a Flea-Borne Rickettsioses Outbreak in Orange County, California

    PubMed Central

    Fogarty, Carrie; Krueger, Laura; Macaluso, Kevin R.; Odhiambo, Antony; Nguyen, Kiet; Farris, Christina M.; Luce-Fedrow, Alison; Bennett, Stephen; Jiang, Ju; Sun, Sokanary; Cummings, Robert F.; Richards, Allen L.

    2016-01-01

    Due to a resurgence of flea-borne rickettsioses in Orange County, California, we investigated the etiologies of rickettsial infections of Ctenocephalides felis, the predominant fleas species obtained from opossums (Didelphis virginiana) and domestic cats (Felis catus), collected from case exposure sites and other areas in Orange County. In addition, we assessed the prevalence of IgG antibodies against spotted fever group (SFGR) and typhus group (TGR) rickettsiae in opossum sera. Of the 597 flea specimens collected from opossums and cats, 37.2% tested positive for Rickettsia. PCR and sequencing of rickettsial genes obtained from C. felis flea DNA preparations revealed the presence of R. typhi (1.3%), R. felis (28.0%) and R. felis-like organisms (7.5%). Sera from opossums contained TGR-specific (40.84%), but not SFGR-specific antibodies. The detection of R. felis and R. typhi in the C. felis fleas in Orange County highlights the potential risk for human infection with either of these pathogens, and underscores the need for further investigations incorporating specimens from humans, animal hosts, and invertebrate vectors in endemic areas. Such studies will be essential for establishing a link in the ongoing flea-borne rickettsioses outbreaks. PMID:27537367

  1. The salmonella transcriptome in lettuce and cilantro soft rot reveals a niche overlap with the animal host intestine.

    PubMed

    Goudeau, Danielle M; Parker, Craig T; Zhou, Yaguang; Sela, Shlomo; Kroupitski, Yulia; Brandl, Maria T

    2013-01-01

    Fresh vegetables have been recurrently associated with salmonellosis outbreaks, and Salmonella contamination of retail produce has been correlated positively with the presence of soft rot disease. We observed that population sizes of Salmonella enterica serovar Typhimurium SL1344 increased 56-fold when inoculated alone onto cilantro leaves, versus 2,884-fold when coinoculated with Dickeya dadantii, a prevalent pathogen that macerates plant tissue. A similar trend in S. enterica populations was observed for soft-rotted lettuce leaves. Transcriptome analysis of S. enterica cells that colonized D. dadantii-infected lettuce and cilantro leaves revealed a clear shift toward anaerobic metabolism and catabolism of substrates that are available due to the degradation of plant cells by the pectinolytic pathogen. Twenty-nine percent of the genes that were upregulated in cilantro macerates were also previously observed to have increased expression levels in the chicken intestine. Furthermore, multiple genes induced in soft rot lesions are also involved in the colonization of mouse, pig, and bovine models of host infection. Among those genes, the operons for ethanolamine and propanediol utilization as well as for the synthesis of cobalamin, a cofactor in these pathways, were the most highly upregulated genes in lettuce and cilantro lesions. In S. Typhimurium strain LT2, population sizes of mutants deficient in propanediol utilization or cobalamin synthesis were 10- and 3-fold lower, respectively, than those of the wild-type strain in macerated cilantro (P < 0.0002); in strain SL1344, such mutants behaved similarly to the parental strain. Anaerobic conditions and the utilization of nutrients in macerated plant tissue that are also present in the animal intestine indicate a niche overlap that may explain the high level of adaptation of S. enterica to soft rot lesions, a common postharvest plant disease.

  2. The Salmonella Transcriptome in Lettuce and Cilantro Soft Rot Reveals a Niche Overlap with the Animal Host Intestine

    PubMed Central

    Goudeau, Danielle M.; Parker, Craig T.; Zhou, Yaguang; Sela, Shlomo; Kroupitski, Yulia

    2013-01-01

    Fresh vegetables have been recurrently associated with salmonellosis outbreaks, and Salmonella contamination of retail produce has been correlated positively with the presence of soft rot disease. We observed that population sizes of Salmonella enterica serovar Typhimurium SL1344 increased 56-fold when inoculated alone onto cilantro leaves, versus 2,884-fold when coinoculated with Dickeya dadantii, a prevalent pathogen that macerates plant tissue. A similar trend in S. enterica populations was observed for soft-rotted lettuce leaves. Transcriptome analysis of S. enterica cells that colonized D. dadantii-infected lettuce and cilantro leaves revealed a clear shift toward anaerobic metabolism and catabolism of substrates that are available due to the degradation of plant cells by the pectinolytic pathogen. Twenty-nine percent of the genes that were upregulated in cilantro macerates were also previously observed to have increased expression levels in the chicken intestine. Furthermore, multiple genes induced in soft rot lesions are also involved in the colonization of mouse, pig, and bovine models of host infection. Among those genes, the operons for ethanolamine and propanediol utilization as well as for the synthesis of cobalamin, a cofactor in these pathways, were the most highly upregulated genes in lettuce and cilantro lesions. In S. Typhimurium strain LT2, population sizes of mutants deficient in propanediol utilization or cobalamin synthesis were 10- and 3-fold lower, respectively, than those of the wild-type strain in macerated cilantro (P < 0.0002); in strain SL1344, such mutants behaved similarly to the parental strain. Anaerobic conditions and the utilization of nutrients in macerated plant tissue that are also present in the animal intestine indicate a niche overlap that may explain the high level of adaptation of S. enterica to soft rot lesions, a common postharvest plant disease. PMID:23104408

  3. International Clostridium difficile animal strain collection and large diversity of animal associated strains

    PubMed Central

    2014-01-01

    Background Clostridium difficile is an important cause of intestinal infections in some animal species and animals might be a reservoir for community associated human infections. Here we describe a collection of animal associated C. difficile strains from 12 countries based on inclusion criteria of one strain (PCR ribotype) per animal species per laboratory. Results Altogether 112 isolates were collected and distributed into 38 PCR ribotypes with agarose based approach and 50 PCR ribotypes with sequencer based approach. Four PCR ribotypes were most prevalent in terms of number of isolates as well as in terms of number of different host species: 078 (14.3% of isolates; 4 hosts), 014/020 (11.6%; 8 hosts); 002 (5.4%; 4 hosts) and 012 (5.4%; 5 hosts). Two animal hosts were best represented; cattle with 31 isolates (20 PCR ribotypes; 7 countries) and pigs with 31 isolates (16 PCR ribotypes; 10 countries). Conclusions This results show that although PCR ribotype 078 is often reported as the major animal C. difficile type, especially in pigs, the variability of strains in pigs and other animal hosts is substantial. Most common human PCR ribotypes (014/020 and 002) are also among most prevalent animal associated C. difficile strains worldwide. The widespread dissemination of toxigenic C. difficile and the considerable overlap in strain distribution between species furthers concerns about interspecies, including zoonotic, transmission of this critically important pathogen. PMID:24972659

  4. Laboratory Evaluation of a Rodenticide-insecticide, Coumavec®, against Rhombomys opimus, the Main Reservoir Host of Zoonotic Cutaneouse Leishmaniasis in Iran

    PubMed Central

    Veysi, Arshad; Vatandoost, Hassan; Arandian, Mohammad Hossein; Jafari, Reza; Yaghoobi-Ershadi, Mohammad Reza; Rassi, Yavar; Akhavan, Amir Ahmad

    2013-01-01

    Background Zoonotic cutaneous leishmaniasis is a growing health problem in many rural areas of Iran. Rhombomys opimus, the great gerbil, is the main animal reservoir of ZCL in the northeast and central part of Iran. The aim of the current study was to evaluate the rodenticidal effect of Coumavec® (a mixture of Coumatetralyl 0.5% and Etofenprox 0.5%) on R. opimus under laboratory condition. Methods: Great gerbils were collected from Sejzi rural district, Esfahan Province, Iran. Four groups of 19 great gerbils were treated with the poisoned baits of different concentrations and one group was considered as control. The bating procedure was conducted in three stages: first, second (a week after first) and third (a month after first stage), in each stage baits were offered in 1 day, based on national protocol for rodent control operation in purpose of ZCL control. Results: The mortality rate for 0.03, 0.0625, 0.125 and 0.25% concentrations in the first stage of baiting were obtained 36.8%, 31.5%, 52.6% and 36.8%, in the second stage 47.3%, 52.6%, 68.4% and 52.6%, and in the third stage 52.6%, 63.1%, 68.4% and 57.8% respectively. The maximum and minimum mortality has occurred in 5–6 days and 31–40 days intervals consequently. Conclusion: The results of this study showed that, Coumavec® has some rodenticidal effects on R. opimus in laboratory condition. For the appropriate rodenticide-insecticide contamination of the rodent body and also considering to the economic issues, we suggest the use of 0.125% concentration for rodent control operation in the field condition. PMID:24409445

  5. Research Strategies to Reduce Tick Densities and the Risk of Tick-borne Disease Transmission through Host-Targeted Control

    Technology Transfer Automated Retrieval System (TEKTRAN)

    While white-tailed deer are not reservoir hosts for the Lyme disease agent, Borrelia burgdorferi, they are the keystone host animal on which adult female blacklegged ticks engorge on blood that is essential to production of tick eggs and completion of the life cycle. This session explores current re...

  6. Subgrouping of ESBL-producing Escherichia coli from animal and human sources: an approach to quantify the distribution of ESBL types between different reservoirs.

    PubMed

    Valentin, Lars; Sharp, Hannah; Hille, Katja; Seibt, Uwe; Fischer, Jennie; Pfeifer, Yvonne; Michael, Geovana Brenner; Nickel, Silke; Schmiedel, Judith; Falgenhauer, Linda; Friese, Anika; Bauerfeind, Rolf; Roesler, Uwe; Imirzalioglu, Can; Chakraborty, Trinad; Helmuth, Reiner; Valenza, Giuseppe; Werner, Guido; Schwarz, Stefan; Guerra, Beatriz; Appel, Bernd; Kreienbrock, Lothar; Käsbohrer, Annemarie

    2014-10-01

    (CTX-M-15) compared to 10.8% of the animal isolates. When grouping data by ESBL types and phylogroups bla(CTX-M-1) genes, mostly combined with phylogroup A or B1, were detected frequently in all settings. In contrast, bla(CTX-M-15) genes common in human and animal populations were mainly combined with phylogroup A, but not with the more virulent phylogroup B2 with the exception of companion animals, where a few isolates were detectable. When E. coli subtype definition included ESBL types, phylogenetic grouping and antimicrobial susceptibility data, the proportion of isolates allocated to common clusters was markedly reduced. Nevertheless, relevant proportions of same subtypes were detected in isolates from the human and livestock and companion animal populations included in this study, suggesting exchange of bacteria or bacterial genes between these populations or a common reservoir. In addition, these results clearly showed that there is some similarity between ESBL genes, and bacterial properties in isolates from the different populations. Finally, our current approach provides good insight into common and population-specific clusters, which can be used as a basis for the selection of ESBL-producing isolates from interesting clusters for further detailed characterizations, e.g. by whole genome sequencing.

  7. Viral antibody dynamics in a chiropteran host.

    PubMed

    Baker, Kate S; Suu-Ire, Richard; Barr, Jennifer; Hayman, David T S; Broder, Christopher C; Horton, Daniel L; Durrant, Christopher; Murcia, Pablo R; Cunningham, Andrew A; Wood, James L N

    2014-03-01

    Bats host many viruses that are significant for human and domestic animal health, but the dynamics of these infections in their natural reservoir hosts remain poorly elucidated. In these, and other, systems, there is evidence that seasonal life-cycle events drive infection dynamics, directly impacting the risk of exposure to spillover hosts. Understanding these dynamics improves our ability to predict zoonotic spillover from the reservoir hosts. To this end, we followed henipavirus antibody levels of >100 individual E. helvum in a closed, captive, breeding population over a 30-month period, using a powerful novel antibody quantitation method. We demonstrate the presence of maternal antibodies in this system and accurately determine their longevity. We also present evidence of population-level persistence of viral infection and demonstrate periods of increased horizontal virus transmission associated with the pregnancy/lactation period. The novel findings of infection persistence and the effect of pregnancy on viral transmission, as well as an accurate quantitation of chiropteran maternal antiviral antibody half-life, provide fundamental baseline data for the continued study of viral infections in these important reservoir hosts.

  8. Life history and demographic drivers of reservoir competence for three tick-borne zoonotic pathogens.

    PubMed

    Ostfeld, Richard S; Levi, Taal; Jolles, Anna E; Martin, Lynn B; Hosseini, Parviez R; Keesing, Felicia

    2014-01-01

    Animal and plant species differ dramatically in their quality as hosts for multi-host pathogens, but the causes of this variation are poorly understood. A group of small mammals, including small rodents and shrews, are among the most competent natural reservoirs for three tick-borne zoonotic pathogens, Borrelia burgdorferi, Babesia microti, and Anaplasma phagocytophilum, in eastern North America. For a group of nine commonly-infected mammals spanning >2 orders of magnitude in body mass, we asked whether life history features or surrogates for (unknown) encounter rates with ticks, predicted reservoir competence for each pathogen. Life history features associated with a fast pace of life generally were positively correlated with reservoir competence. However, a model comparison approach revealed that host population density, as a proxy for encounter rates between hosts and pathogens, generally received more support than did life history features. The specific life history features and the importance of host population density differed somewhat between the different pathogens. We interpret these results as supporting two alternative but non-exclusive hypotheses for why ecologically widespread, synanthropic species are often the most competent reservoirs for multi-host pathogens. First, multi-host pathogens might adapt to those hosts they are most likely to experience, which are likely to be the most abundant and/or frequently bitten by tick vectors. Second, species with fast life histories might allocate less to certain immune defenses, which could increase their reservoir competence. Results suggest that of the host species that might potentially be exposed, those with comparatively high population densities, small bodies, and fast pace of life will often be keystone reservoirs that should be targeted for surveillance or management.

  9. Isolation of Tick and Mosquito-Borne Arboviruses from Ticks Sampled from Livestock and Wild Animal Hosts in Ijara District, Kenya

    PubMed Central

    Lutomiah, Joel; Obanda, Vincent; Gakuya, Francis; Mutisya, James; Mulwa, Francis; Michuki, George; Chepkorir, Edith; Fischer, Anne; Venter, Marietjie; Sang, Rosemary

    2013-01-01

    Abstract Tick-borne viruses infect humans through the bite of infected ticks during opportunistic feeding or through crushing of ticks by hand and, in some instances, through contact with infected viremic animals. The Ijara District, an arid to semiarid region in northern Kenya, is home to a pastoralist community for whom livestock keeping is a way of life. Part of the Ijara District lies within the boundaries of a Kenya Wildlife Service–protected conservation area. Arbovirus activity among mosquitoes, animals, and humans is reported in the region, mainly because prevailing conditions necessitate that people continuously move their animals in search of pasture, bringing them in contact with ongoing arbovirus transmission cycles. To identify the tick-borne viruses circulating among these communities, we analyzed ticks sampled from diverse animal hosts. A total of 10,488 ticks were sampled from both wildlife and livestock hosts and processed in 1520 pools of up to eight ticks per pool. The sampled ticks were classified to species, processed for virus screening by cell culture using Vero cells and RT-PCR (in the case of Hyalomma species), followed by amplicon sequencing. The tick species sampled included Rhipicephalus pulchellus (76.12%), Hyalomma truncatum (8.68%), Amblyomma gemma (5.00%), Amblyomma lepidum (4.34%), and others (5.86%). We isolated and identified Bunyamwera (44), Dugbe (5), Ndumu (2), Semliki forest (25), Thogoto (3), and West Nile (3) virus strains. This observation constitutes a previously unreported detection of mosquito-borne Semliki forest and Bunyamwera viruses in ticks, and association of West Nile virus with A. gemma and Rh. pulchellus ticks. These findings provide additional evidence on the potential role of ticks and associated animals in the circulation of diverse arboviruses in northeastern Kenya, including viruses previously known to be essentially mosquito borne. PMID:23805790

  10. Ferrets as a Novel Animal Model for Studying Human Respiratory Syncytial Virus Infections in Immunocompetent and Immunocompromised Hosts

    PubMed Central

    Stittelaar, Koert J.; de Waal, Leon; van Amerongen, Geert; Veldhuis Kroeze, Edwin J.B.; Fraaij, Pieter L.A.; van Baalen, Carel A.; van Kampen, Jeroen J.A.; van der Vries, Erhard; Osterhaus, Albert D.M.E.; de Swart, Rik L.

    2016-01-01

    Human respiratory syncytial virus (HRSV) is an important cause of severe respiratory tract disease in immunocompromised patients. Animal models are indispensable for evaluating novel intervention strategies in this complex patient population. To complement existing models in rodents and non-human primates, we have evaluated the potential benefits of an HRSV infection model in ferrets (Mustela putorius furo). Nine- to 12-month-old HRSV-seronegative immunocompetent or immunocompromised ferrets were infected with a low-passage wild-type strain of HRSV subgroup A (105 TCID50) administered by intra-tracheal or intra-nasal inoculation. Immune suppression was achieved by bi-daily oral administration of tacrolimus, mycophenolate mofetil, and prednisolone. Throat and nose swabs were collected daily and animals were euthanized four, seven, or 21 days post-infection (DPI). Virus loads were determined by quantitative virus culture and qPCR. We observed efficient HRSV replication in both the upper and lower respiratory tract. In immunocompromised ferrets, virus loads reached higher levels and showed delayed clearance as compared to those in immunocompetent animals. Histopathological evaluation of animals euthanized 4 DPI demonstrated that the virus replicated in the respiratory epithelial cells of the trachea, bronchi, and bronchioles. These animal models can contribute to an assessment of the efficacy and safety of novel HRSV intervention strategies. PMID:27314379

  11. Ferrets as a Novel Animal Model for Studying Human Respiratory Syncytial Virus Infections in Immunocompetent and Immunocompromised Hosts.

    PubMed

    Stittelaar, Koert J; de Waal, Leon; van Amerongen, Geert; Veldhuis Kroeze, Edwin J B; Fraaij, Pieter L A; van Baalen, Carel A; van Kampen, Jeroen J A; van der Vries, Erhard; Osterhaus, Albert D M E; de Swart, Rik L

    2016-06-14

    Human respiratory syncytial virus (HRSV) is an important cause of severe respiratory tract disease in immunocompromised patients. Animal models are indispensable for evaluating novel intervention strategies in this complex patient population. To complement existing models in rodents and non-human primates, we have evaluated the potential benefits of an HRSV infection model in ferrets (Mustela putorius furo). Nine- to 12-month-old HRSV-seronegative immunocompetent or immunocompromised ferrets were infected with a low-passage wild-type strain of HRSV subgroup A (10⁵ TCID50) administered by intra-tracheal or intra-nasal inoculation. Immune suppression was achieved by bi-daily oral administration of tacrolimus, mycophenolate mofetil, and prednisolone. Throat and nose swabs were collected daily and animals were euthanized four, seven, or 21 days post-infection (DPI). Virus loads were determined by quantitative virus culture and qPCR. We observed efficient HRSV replication in both the upper and lower respiratory tract. In immunocompromised ferrets, virus loads reached higher levels and showed delayed clearance as compared to those in immunocompetent animals. Histopathological evaluation of animals euthanized 4 DPI demonstrated that the virus replicated in the respiratory epithelial cells of the trachea, bronchi, and bronchioles. These animal models can contribute to an assessment of the efficacy and safety of novel HRSV intervention strategies.

  12. Evidence for Personal Protective Measures to Reduce Human Contact With Blacklegged Ticks and for Environmentally Based Control Methods to Suppress Host-Seeking Blacklegged Ticks and Reduce Infection with Lyme Disease Spirochetes in Tick Vectors and Rodent Reservoirs.

    PubMed

    Eisen, Lars; Dolan, Marc C

    2016-07-20

    In the 1980s, the blacklegged tick, Ixodes scapularis Say, and rodents were recognized as the principal vector and reservoir hosts of the Lyme disease spirochete Borrelia burgdorferi in the eastern United States, and deer were incriminated as principal hosts for I. scapularis adults. These realizations led to pioneering studies aiming to reduce the risk for transmission of B. burgdorferi to humans by attacking host-seeking ticks with acaricides, interrupting the enzootic transmission cycle by killing immatures infesting rodent reservoirs by means of acaricide-treated nesting material, or reducing deer abundance to suppress tick numbers. We review the progress over the past three decades in the fields of: 1) prevention of human-tick contact with repellents and permethrin-treated clothing, and 2) suppression of I. scapularis and disruption of enzootic B. burgdorferi transmission with environmentally based control methods. Personal protective measures include synthetic and natural product-based repellents that can be applied to skin and clothing, permethrin sprays for clothing and gear, and permethrin-treated clothing. A wide variety of approaches and products to suppress I. scapularis or disrupt enzootic B. burgdorferi transmission have emerged and been evaluated in field trials. Application of synthetic chemical acaricides is a robust method to suppress host-seeking I. scapularis ticks within a treated area for at least 6-8 wk. Natural product-based acaricides or entomopathogenic fungi have emerged as alternatives to kill host-seeking ticks for homeowners who are unwilling to use synthetic chemical acaricides. However, as compared with synthetic chemical acaricides, these approaches appear less robust in terms of both their killing efficacy and persistence. Use of rodent-targeted topical acaricides represents an alternative for homeowners opposed to open distribution of acaricides to the ground and vegetation on their properties. This host-targeted approach also

  13. Genetic characterization of the human relapsing fever spirochete Borrelia miyamotoi in vectors and animal reservoirs of Lyme disease spirochetes in France

    PubMed Central

    2014-01-01

    Background In France as elsewhere in Europe the most prevalent TBD in humans is Lyme borreliosis, caused by different bacterial species belonging to Borrelia burgdorferi sensu lato complex and transmitted by the most important tick species in France, Ixodes ricinus. However, the diagnosis of Lyme disease is not always confirmed and unexplained syndromes occurring after tick bites have become an important issue. Recently, B. miyamotoi belonging to the relapsing fever group and transmitted by the same Ixodes species has been involved in human disease in Russia, the USA and the Netherlands. In the present study, we investigate the presence of B. miyamotoi along with other Lyme Borreliosis spirochetes, in ticks and possible animal reservoirs collected in France. Methods We analyzed 268 ticks (Ixodes ricinus) and 72 bank voles (Myodes glareolus) collected and trapped in France for the presence of DNA from B. miyamotoi as well as from Lyme spirochetes using q-PCR and specific primers and probes. We then compared the French genotypes with those found in other European countries. Results We found that 3% of ticks and 5.55% of bank voles were found infected by the same B. miyamotoi genotype, while co-infection with other Lyme spirochetes (B. garinii) was identified in 12% of B. miyamotoi infected ticks. Sequencing showed that ticks and rodents carried the same genotype as those recently characterized in a sick person in the Netherlands. Conclusions The genotype of B. miyamotoi circulating in ticks and bank voles in France is identical to those already described in ticks from Western Europe and to the genotype isolated from a sick person in The Netherlands. This results suggests that even though no human cases have been reported in France, surveillance has to be improved. Moreover, we showed that ticks could simultaneously carry B. miyamotoi and Lyme disease spirochetes, increasing the problem of co-infection in humans. PMID:24886071

  14. Genetic characterization of flea-derived Bartonella species from native animals in Australia suggests host-parasite co-evolution.

    PubMed

    Kaewmongkol, Gunn; Kaewmongkol, Sarawan; McInnes, Linda M; Burmej, Halina; Bennett, Mark D; Adams, Peter J; Ryan, Una; Irwin, Peter J; Fenwick, Stanley G

    2011-12-01

    Fleas are important arthropod vectors for a variety of diseases in veterinary and human medicine, and bacteria belonging to the genus Bartonella are among the organisms most commonly transmitted by these ectoparasites. Recently, a number of novel Bartonella species and novel species candidates have been reported in marsupial fleas in Australia. In the present study the genetic diversity of marsupial fleas was investigated; 10 species of fleas were collected from seven different marsupial and placental mammal hosts in Western Australia including woylies (Bettongia penicillata), western barred bandicoots (Perameles bougainville), mardos (Antechinus flavipes), bush rats (Rattus fuscipes), red foxes (Vulpes vulpes), feral cats (Felis catus) and rabbits (Oryctolagus cuniculus). PCR and sequence analysis of the cytochrome oxidase subunit I (COI) and the 18S rRNA genes from these fleas was performed. Concatenated phylogenetic analysis of the COI and 18S rRNA genes revealed a close genetic relationship between marsupial fleas, with Pygiopsylla hilli from woylies, Pygiopsylla tunneyi from western barred bandicoots and Acanthopsylla jordani from mardos, forming a separate cluster from fleas collected from the placental mammals in the same geographical area. The clustering of Bartonella species with their marsupial flea hosts suggests co-evolution of marsupial hosts, marsupial fleas and Bartonella species in Australia.

  15. Peptidoglycan induces loss of a nuclear peptidoglycan recognition protein during host tissue development in a beneficial animal-bacterial symbiosis.

    PubMed

    Troll, Joshua V; Adin, Dawn M; Wier, Andrew M; Paquette, Nicholas; Silverman, Neal; Goldman, William E; Stadermann, Frank J; Stabb, Eric V; McFall-Ngai, Margaret J

    2009-07-01

    Peptidoglycan recognition proteins (PGRPs) are mediators of innate immunity and recently have been implicated in developmental regulation. To explore the interplay between these two roles, we characterized a PGRP in the host squid Euprymna scolopes (EsPGRP1) during colonization by the mutualistic bacterium Vibrio fischeri. Previous research on the squid-vibrio symbiosis had shown that, upon colonization of deep epithelium-lined crypts of the host light organ, symbiont-derived peptidoglycan monomers induce apoptosis-mediated regression of remote epithelial fields involved in the inoculation process. In this study, immunofluorescence microscopy revealed that EsPGRP1 localizes to the nuclei of epithelial cells, and symbiont colonization induces the loss of EsPGRP1 from apoptotic nuclei. The loss of nuclear EsPGRP1 occurred prior to DNA cleavage and breakdown of the nuclear membrane, but followed chromatin condensation, suggesting that it occurs during late-stage apoptosis. Experiments with purified peptidoglycan monomers and with V. fischeri mutants defective in peptidoglycan-monomer release provided evidence that these molecules trigger nuclear loss of EsPGRP1 and apoptosis. The demonstration of a nuclear PGRP is unprecedented, and the dynamics of EsPGRP1 during apoptosis provide a striking example of a connection between microbial recognition and developmental responses in the establishment of symbiosis.

  16. CRN13 candidate effectors from plant and animal eukaryotic pathogens are DNA-binding proteins which trigger host DNA damage response.

    PubMed

    Ramirez-Garcés, Diana; Camborde, Laurent; Pel, Michiel J C; Jauneau, Alain; Martinez, Yves; Néant, Isabelle; Leclerc, Catherine; Moreau, Marc; Dumas, Bernard; Gaulin, Elodie

    2016-04-01

    To successfully colonize their host, pathogens produce effectors that can interfere with host cellular processes. Here we investigated the function of CRN13 candidate effectors produced by plant pathogenic oomycetes and detected in the genome of the amphibian pathogenic chytrid fungus Batrachochytrium dendrobatidis (BdCRN13). When expressed in Nicotiana, AeCRN13, from the legume root pathogen Aphanomyces euteiches, increases the susceptibility of the leaves to the oomycete Phytophthora capsici. When transiently expressed in amphibians or plant cells, AeCRN13 and BdCRN13 localize to the cell nuclei, triggering aberrant cell development and eventually causing cell death. Using Förster resonance energy transfer experiments in plant cells, we showed that both CRN13s interact with nuclear DNA and trigger plant DNA damage response (DDR). Mutating key amino acid residues in a predicted HNH-like endonuclease motif abolished the interaction of AeCRN13 with DNA, the induction of DDR and the enhancement of Nicotiana susceptibility to P. capsici. Finally, H2AX phosphorylation, a marker of DNA damage, and enhanced expression of genes involved in the DDR were observed in A. euteiches-infected Medicago truncatula roots. These results show that CRN13 from plant and animal eukaryotic pathogens promotes host susceptibility by targeting nuclear DNA and inducing DDR.

  17. Epidemiology of brucellosis in domestic animals caused by Brucella melitensis, Brucella suis and Brucella abortus.

    PubMed

    Díaz Aparicio, E

    2013-04-01

    Brucellosis is a disease that causes severe economic losses for livestock farms worldwide. Brucella melitensis, B. abortus and B. suis, which are transmitted between animals both vertically and horizontally, cause abortion and infertility in their primary natural hosts - goats and sheep (B. melitensis), cows (B. abortus) and sows (B. suis). Brucella spp. infect not only their preferred hosts but also other domestic and wild animal species, which in turn can act as reservoirs of the disease for other animal species and humans. Brucellosis is therefore considered to be a major zoonosis transmitted by direct contact with animals and/or their secretions, or by consuming milk and dairy products.

  18. Mesenchymal stem cells provide prophylaxis against acute graft-versus-host disease following allogeneic hematopoietic stem cell transplantation: A meta-analysis of animal models.

    PubMed

    Wang, Li; Zhang, Haiyan; Guan, Lixun; Zhao, Shasha; Gu, Zhenyang; Wei, Huaping; Gao, Zhe; Wang, Feiyan; Yang, Nan; Luo, Lan; Li, Yonghui; Wang, Lili; Liu, Daihong; Gao, Chunji

    2016-09-20

    A meta-analysis of animal models was conducted to evaluate the prophylactic effects of mesenchymal stem cells (MSCs) on acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation. A total of 50 studies involving 1848 animals were included. The pooled results showed that MSCs significantly reduced aGVHD-associated mortality (risk ratio = 0.70, 95% confidence interval 0.62 to 0.79, P = 2.73×10-9) and clinical scores (standardized mean difference = -3.60, 95% confidence interval -4.43 to -2.76, P = 3.61×10-17). In addition, MSCs conferred robust favorable prophylactic effects on aGVHD across recipient species, MSC doses, and administration times, but not MSC sources. Our meta-analysis showed that MSCs significantly prevented mortality and alleviated the clinical manifestations of aGVHD in animal models. These data support further clinical trials aimed at evaluating the efficacy of using MSCs to prevent aGVHD.

  19. Dissecting the Interplay Between Intestinal Microbiota and Host Immunity in Health and Disease: Lessons Learned from Germfree and Gnotobiotic Animal Models

    PubMed Central

    Fiebiger, Ulrike; Bereswill, Stefan; Heimesaat, Markus M.

    2016-01-01

    This review elaborates the development of germfree and gnotobiotic animal models and their application in the scientific field to unravel mechanisms underlying host–microbe interactions and distinct diseases. Strictly germfree animals are raised in isolators and not colonized by any organism at all. The germfree state is continuously maintained by birth, raising, housing and breeding under strict sterile conditions. However, isolator raised germfree mice are exposed to a stressful environment and exert an underdeveloped immune system. To circumvent these physiological disadvantages depletion of the bacterial microbiota in conventionally raised and housed mice by antibiotic treatment has become an alternative approach. While fungi and parasites are not affected by antibiosis, the bacterial microbiota in these “secondary abiotic mice” have been shown to be virtually eradicated. Recolonization of isolator raised germfree animals or secondary abiotic mice results in a gnotobiotic state. Both, germfree and gnotobiotic mice have been successfully used to investigate biological functions of the conventional microbiota in health and disease. Particularly for the development of novel clinical applications germfree mice are widely used tools, as summarized in this review further focusing on the modulation of bacterial microbiota in laboratory mice to better mimic conditions in the human host. PMID:27980855

  20. Plant subviral RNAs as a long noncoding RNA (lncRNA): Analogy with animal lncRNAs in host-virus interactions.

    PubMed

    Shimura, Hanako; Masuta, Chikara

    2016-01-02

    Satellite RNAs (satRNAs) and viroids belong to the group called subviral agents and are the smallest pathogens of plants. In general, small satRNAs and viroids are 300-400 nt in size and do not encode any functional proteins; they are thus regarded as so-called long noncoding RNAs (lncRNAs). These lncRNAs are receiving great attention as a new RNA class involved in gene regulation to control important biological processes such as gene transcription and epigenetic regulation. A substantial number of lncRNAs in animal cells have been found to play important roles in the interactions between a virus and its host. We here discuss the pathogenicity of subviral RNAs (especially satRNAs) in plant cells and their functions as lncRNAs associated with viral diseases, using animal lncRNAs as an analogy. Because, unlike animal lncRNAs, plant subviral RNAs can replicate and accumulate at very high levels in infected cells, we here considered the unique possibility that the RNA silencing machinery of plants, an important defense mechanism against virus infection, may have brought about the replication ability of subviral molecules. In addition, we also discuss the possibility that satRNAs may have arisen from plant-virus interactions in virus-infected cells. Understanding the molecular functions of these unique lncRNAs in plants will enable us to reveal the most plausible origins of these subviral RNAs.

  1. Mesenchymal stem cells provide prophylaxis against acute graft-versus-host disease following allogeneic hematopoietic stem cell transplantation: A meta-analysis of animal models

    PubMed Central

    Guan, Lixun; Zhao, Shasha; Gu, Zhenyang; Wei, Huaping; Gao, Zhe; Wang, Feiyan; Yang, Nan; Luo, Lan; Li, Yonghui; Wang, Lili; Liu, Daihong; Gao, Chunji

    2016-01-01

    A meta-analysis of animal models was conducted to evaluate the prophylactic effects of mesenchymal stem cells (MSCs) on acute graft-versus-host disease (aGVHD) after allogeneic hematopoietic stem cell transplantation. A total of 50 studies involving 1848 animals were included. The pooled results showed that MSCs significantly reduced aGVHD-associated mortality (risk ratio = 0.70, 95% confidence interval 0.62 to 0.79, P = 2.73×10−9) and clinical scores (standardized mean difference = −3.60, 95% confidence interval −4.43 to −2.76, P = 3.61×10−17). In addition, MSCs conferred robust favorable prophylactic effects on aGVHD across recipient species, MSC doses, and administration times, but not MSC sources. Our meta-analysis showed that MSCs significantly prevented mortality and alleviated the clinical manifestations of aGVHD in animal models. These data support further clinical trials aimed at evaluating the efficacy of using MSCs to prevent aGVHD. PMID:27528221

  2. Varicella zoster virus-induced pain and post-herpetic neuralgia in the human host and in rodent animal models.

    PubMed

    Kinchington, Paul R; Goins, William F

    2011-12-01

    Pain and post-herpetic neuralgia (PHN) are common and highly distressing complications of herpes zoster that remain a significant public health concern and in need of improved therapies. Zoster results from reactivation of the herpesvirus varicella zoster virus (VZV) from a neuronal latent state established at the primary infection (varicella). PHN occurs in some one fifth to one third of zoster cases with severity, incidence, and duration of pain increasing with rising patient age. While VZV reactivation and the ensuing ganglionic damage trigger the pain response, the mechanisms underlying protracted PHN are not understood, and the lack of an animal model of herpes zoster (reactivation) makes this issue more challenging. A recent preclinical rodent model has developed that opens up the potential to allow the exploration of the underlying mechanisms and treatments for VZV-induced pain. Rats inoculated with live cell-associated human VZV into the hind paw reliably demonstrate thermal hyperalgesia and mechanical allodynia for extended periods and then spontaneously recover. Dorsal root ganglia express a limited VZV gene subset, including the IE62 regulatory protein, and upregulate expression of markers suggesting a neuropathic pain state. The model has been used to investigate treatment modalities and aspects of pain signaling and is under investigation by the authors to delineate VZV genetics involved in the induction of pain. This article compares human zoster-associated pain and PHN to the pain indicators in the rat and poses important questions that, if answered, could be the basis for new treatments.

  3. Assessment of vector/host contact: comparison of animal-baited traps and UV-light/suction trap for collecting Culicoides biting midges (Diptera: Ceratopogonidae), vectors of Orbiviruses

    PubMed Central

    2011-01-01

    Background The emergence and massive spread of bluetongue in Western Europe during 2006-2008 had disastrous consequences for sheep and cattle production and confirmed the ability of Palaearctic Culicoides (Diptera: Ceratopogonidae) to transmit the virus. Some aspects of Culicoides ecology, especially host-seeking and feeding behaviors, remain insufficiently described due to the difficulty of collecting them directly on a bait animal, the most reliable method to evaluate biting rates. Our aim was to compare typical animal-baited traps (drop trap and direct aspiration) to both a new sticky cover trap and a UV-light/suction trap (the most commonly used method to collect Culicoides). Methods/results Collections were made from 1.45 hours before sunset to 1.45 hours after sunset in June/July 2009 at an experimental sheep farm (INRA, Nouzilly, Western France), with 3 replicates of a 4 sites × 4 traps randomized Latin square using one sheep per site. Collected Culicoides individuals were sorted morphologically to species, sex and physiological stages for females. Sibling species were identified using a molecular assay. A total of 534 Culicoides belonging to 17 species was collected. Abundance was maximal in the drop trap (232 females and 4 males from 10 species) whereas the diversity was the highest in the UV-light/suction trap (136 females and 5 males from 15 species). Significant between-trap differences abundance and parity rates were observed. Conclusions Only the direct aspiration collected exclusively host-seeking females, despite a concern that human manipulation may influence estimation of the biting rate. The sticky cover trap assessed accurately the biting rate of abundant species even if it might act as an interception trap. The drop trap collected the highest abundance of Culicoides and may have caught individuals not attracted by sheep but by its structure. Finally, abundances obtained using the UV-light/suction trap did not estimate accurately Culicoides

  4. Sylvatic echinococcosis in Argentina. I. On the morphology and biology of strobilar Echinococcus granulosus (Batsch, 1786) from domestic and sylvatic animal hosts.

    PubMed

    Schantz, P M; Cruz-Reyes, A; Colli, C; Lord, R D

    1975-09-01

    Dogs were fed larvae of Echinococcus granulosus (Batsch, 1786) recovered from sheep in Argentina. The morphological characteristics of strobilae recovered from dogs at 28, 60 and 76 days postexposure were compared with those of Echinococcus spp. recovered from naturally infected foxes, Dusicyon clupaeus (Molina) and D. griseus (Gray), and those of worms reared in dogs from larvae in European hares, Lepus europaeus (L.). Only slight differences were observed in characters of taxonomic importance and it was concluded that all cestodes represented a single species, E. granulosus. The results are discussed as they bear on the speciation controversy and the potential epidemiology importance of Dusicyon spp. as hosts of E. granulosus. It was suggested that E. patagonicus Szidat, 1960 previously described from D. culpaeus is conspecific with E. granulosus. E. cepanzoi Szidat, 1971 is probably also a synonym of E. granulosus and the subspecies E. g. dusicyontis Blood and Lelijveld, 1969, is rejected on the grounds that there is no evidence for host specificity and ecological or other segregation from the nominate form. Foxes appear to become infected from scavenging on dead sheep in localities where E. granulosus is endemic in domestic animals. There is still no evidence that E. granulosus is maintained in Argentina in sylvatic cycles.

  5. STUDIES ON LEPTOSPIROSIS IN THAILAND, WITH SPECIAL REFERENCE TO THE EPIDEMIOLOGY, PATHOLOGY AND CLINICAL ASPECTS, AND ITS RELATION TO THE ANIMAL RESERVOIR HOSTS

    DTIC Science & Technology

    and the results indicated that the incidence was slightly increased (from 4% to be 6% and 9% respectively). Surveys of leptospiral antibodies in Umong...studies at Pitsanuloke Province enabled the author to find out an endemic area and revealed five leptospiral serogroups were prevalent in Pitsanuloke

  6. Selected examples of dispersal of arthropods associated with agricultural crop and animal production

    NASA Technical Reports Server (NTRS)

    Henneberry, T. J.

    1979-01-01

    The economic importance of arthropods in agricultural production systems and the possibilities of using dispersal behavior to develop and manipulate control are examined. Examples of long and short distance dispersal of economic insect pests and beneficial species from cool season host reservoirs and overwintering sites are presented. Significant dispersal of these species often occurring during crop and animal production is discussed.

  7. Southern plains woodrats (Neotoma micropus) from southern Texas are important reservoirs of two genotypes of Trypanosoma cruzi and host of a putative novel Trypanosoma species.

    PubMed

    Charles, Roxanne A; Kjos, Sonia; Ellis, Angela E; Barnes, John C; Yabsley, Michael J

    2013-01-01

    Trypanosoma cruzi, the causative agent of Chagas' disease, is an important public health and veterinary pathogen. Although human cases are rare in the United States, infections in wildlife, and in some areas domestic dogs, are common. In 2008 and 2010, we investigated T. cruzi prevalence in possible vertebrate reservoirs in southern Texas, with an emphasis on southern plains woodrats (Neotoma micropus). Infection status was determined using a combination of culture isolation, polymerase chain reaction (PCR), and serologic testing. Based on PCR and/or culture, T. cruzi was detected in 35 of 104 (34%) woodrats, 3 of 4 (75%) striped skunks (Mephitis mephitis), 12 of 20 (60%) raccoons (Procyon lotor), and 5 of 28 (18%) other rodents including a hispid cotton rat (Sigmodon hispidus), rock squirrel (Otospermophilus variegatus), black rat (Rattus rattus), and two house mice (Mus musculus). Additionally, another Trypanosoma species was detected in 41 woodrats, of which 27 were co-infected with T. cruzi. Genetic characterization of T. cruzi revealed that raccoon, rock squirrel, and cotton rat isolates were genotype TcIV, while woodrats and skunks were infected with TcI and TcIV. Based on the Chagas Stat-Pak assay, antibodies were detected in 27 woodrats (26%), 13 raccoons (65%), 4 skunks (100%), and 5 other rodents (18%) (two white-ankled mice [Peromyscus pectoralis laceianus], two house mice, and a rock squirrel). Seroprevalence based on indirect immunofluorescence antibody testing was higher for both woodrats (37%) and raccoons (90%), compared with the Chagas Stat-Pak. This is the first report of T. cruzi in a hispid cotton rat, black rat, rock squirrel, and white-ankled mouse. These data indicate that based on culture and PCR testing, the prevalence of T. cruzi in woodrats is comparable with other common reservoirs (i.e., raccoons and opossums) in the United States. However, unlike raccoons and opossums, which tend to be infected with a particular genotype, southern

  8. Different carbon reservoirs of auriferous fluids in African Archean and Proterozoic gold deposits? Constraints from stable carbon isotopic compositions of quartz-hosted CO2-rich fluid inclusions

    NASA Astrophysics Data System (ADS)

    Lüders, Volker; Klemd, Reiner; Oberthür, Thomas; Plessen, Birgit

    2015-04-01

    Stable carbon (and when present, nitrogen) isotope ratios of fluid inclusions in quartz from selected gold deposits in Ghana and Zimbabwe have been analyzed using a crushing device interfaced to an isotopic ratio mass spectrometer (IRMS) in order to constrain possible sources of the auriferous fluids. The study revealed a striking difference in stable carbon isotopic compositions of CO2 in quartz-hosted fluid inclusions from Archean and Paleoproterozoic orogenic gold deposits and points to diverse sources of CO2 in the studied deposits. Whether this finding can be generalized for other Archean and Proterozoic orogenic gold deposits worldwide remains open. However, a significant CO2 contribution by mantle degassing can be ruled out for every deposit studied. Devolatilization of greenstone belt rocks is the most likely source for CO2 in some Archean Au deposits in Zimbabwe, whereas CO2 in Proterozoic vein-type Au deposits in the West African Craton is most likely derived from Corg-bearing metasedimentary rocks. The δ13CCO2 values of high-density CO2-rich, water-poor inclusions hosted in quartz pebbles from the world-class Au-bearing conglomerate deposits at Tarkwa (Ghana) differ considerably from the δ13CCO2 values of similar high-density CO2-rich inclusions in vein quartz from the giant Ashanti deposit (Ghana) and disprove the idea of derivation of the Tarkwaian quartz (and gold?) from an older equivalent to the Ashanti vein-type gold deposit.

  9. [Zoonotic diseases caused by bacteria of the genus Bartonella genus: new reservoirs ? New vectors?].

    PubMed

    Chomel, Bruno B; Boulouis, Henri-Jean

    2005-03-01

    Domestic animals and wildlife represent a large reservoir for bartonellae, at least eight species or subspecies of which have been reported to cause zoonotic infections. In addition, numerous orphan clinical syndromes are now being attributed to Bartonella henselae infection. Many mammalian species, including cats, dogs, rodents and ruminants are the main bartonellae reservoirs. Cats are the main reservoir for B. henselae. It appears that domestic dogs, at least in non tropical regions, are more likely to be accidental hosts than reservoirs, and constitute excellent sentinels for human infections. Bartonellae are vector-borne bacteria. The mode of B. henselae transmission by cat fleas is now better understood, but new potential vectors have recently been identified, including ticks and biting flies. This articles summarizes current knowledge of the etiology, new clinical features and epidemiological characteristics of these emerging zoonoses.

  10. Seawater is a reservoir of multi-resistant Escherichia coli, including strains hosting plasmid-mediated quinolones resistance and extended-spectrum beta-lactamases genes.

    PubMed

    Alves, Marta S; Pereira, Anabela; Araújo, Susana M; Castro, Bruno B; Correia, António C M; Henriques, Isabel

    2014-01-01

    The aim of this study was to examine antibiotic resistance (AR) dissemination in coastal water, considering the contribution of different sources of fecal contamination. Samples were collected in Berlenga, an uninhabited island classified as Natural Reserve and visited by tourists for aquatic recreational activities. To achieve our aim, AR in Escherichia coli isolates from coastal water was compared to AR in isolates from two sources of fecal contamination: human-derived sewage and seagull feces. Isolation of E. coli was done on Chromocult agar. Based on genetic typing 414 strains were established. Distribution of E. coli phylogenetic groups was similar among isolates of all sources. Resistances to streptomycin, tetracycline, cephalothin, and amoxicillin were the most frequent. Higher rates of AR were found among seawater and feces isolates, except for last-line antibiotics used in human medicine. Multi-resistance rates in isolates from sewage and seagull feces (29 and 32%) were lower than in isolates from seawater (39%). Seawater AR profiles were similar to those from seagull feces and differed significantly from sewage AR profiles. Nucleotide sequences matching resistance genes bla TEM, sul1, sul2, tet(A), and tet(B), were present in isolates of all sources. Genes conferring resistance to 3rd generation cephalosporins were detected in seawater (bla CTX-M-1 and bla SHV-12) and seagull feces (bla CMY-2). Plasmid-mediated determinants of resistance to quinolones were found: qnrS1 in all sources and qnrB19 in seawater and seagull feces. Our results show that seawater is a relevant reservoir of AR and that seagulls are an efficient vehicle to spread human-associated bacteria and resistance genes. The E. coli resistome recaptured from Berlenga coastal water was mainly modulated by seagulls-derived fecal pollution. The repertoire of resistance genes covers antibiotics critically important for humans, a potential risk for human health.

  11. Seawater is a reservoir of multi-resistant Escherichia coli, including strains hosting plasmid-mediated quinolones resistance and extended-spectrum beta-lactamases genes

    PubMed Central

    Alves, Marta S.; Pereira, Anabela; Araújo, Susana M.; Castro, Bruno B.; Correia, António C. M.; Henriques, Isabel

    2014-01-01

    The aim of this study was to examine antibiotic resistance (AR) dissemination in coastal water, considering the contribution of different sources of fecal contamination. Samples were collected in Berlenga, an uninhabited island classified as Natural Reserve and visited by tourists for aquatic recreational activities. To achieve our aim, AR in Escherichia coli isolates from coastal water was compared to AR in isolates from two sources of fecal contamination: human-derived sewage and seagull feces. Isolation of E. coli was done on Chromocult agar. Based on genetic typing 414 strains were established. Distribution of E. coli phylogenetic groups was similar among isolates of all sources. Resistances to streptomycin, tetracycline, cephalothin, and amoxicillin were the most frequent. Higher rates of AR were found among seawater and feces isolates, except for last-line antibiotics used in human medicine. Multi-resistance rates in isolates from sewage and seagull feces (29 and 32%) were lower than in isolates from seawater (39%). Seawater AR profiles were similar to those from seagull feces and differed significantly from sewage AR profiles. Nucleotide sequences matching resistance genes blaTEM, sul1, sul2, tet(A), and tet(B), were present in isolates of all sources. Genes conferring resistance to 3rd generation cephalosporins were detected in seawater (blaCTX-M-1 and blaSHV-12) and seagull feces (blaCMY-2). Plasmid-mediated determinants of resistance to quinolones were found: qnrS1 in all sources and qnrB19 in seawater and seagull feces. Our results show that seawater is a relevant reservoir of AR and that seagulls are an efficient vehicle to spread human-associated bacteria and resistance genes. The E. coli resistome recaptured from Berlenga coastal water was mainly modulated by seagulls-derived fecal pollution. The repertoire of resistance genes covers antibiotics critically important for humans, a potential risk for human health. PMID:25191308

  12. Bat–man disease transmission: zoonotic pathogens from wildlife reservoirs to human populations

    PubMed Central

    Allocati, N; Petrucci, A G; Di Giovanni, P; Masulli, M; Di Ilio, C; De Laurenzi, V

    2016-01-01

    Bats are natural reservoir hosts and sources of infection of several microorganisms, many of which cause severe human diseases. Because of contact between bats and other animals, including humans, the possibility exists for additional interspecies transmissions and resulting disease outbreaks. The purpose of this article is to supply an overview on the main pathogens isolated from bats that have the potential to cause disease in humans. PMID:27551536

  13. One Health and Food-Borne Disease: Salmonella Transmission between Humans, Animals, and Plants.

    PubMed

    Silva, Claudia; Calva, Edmundo; Maloy, Stanley

    2014-02-01

    There are >2,600 recognized serovars of Salmonella enterica. Many of these Salmonella serovars have a broad host range and can infect a wide variety of animals, including mammals, birds, reptiles, amphibians, fish, and insects. In addition, Salmonella can grow in plants and can survive in protozoa, soil, and water. Hence, broad-host-range Salmonella can be transmitted via feces from wild animals, farm animals, and pets or by consumption of a wide variety of common foods: poultry, beef, pork, eggs, milk, fruit, vegetables, spices, and nuts. Broad-host-range Salmonella pathogens typically cause gastroenteritis in humans. Some Salmonella serovars have a more restricted host range that is associated with changes in the virulence plasmid pSV, accumulation of pseudogenes, and chromosome rearrangements. These changes in host-restricted Salmonella alter pathogen-host interactions such that host-restricted Salmonella organisms commonly cause systemic infections and are transmitted between host populations by asymptomatic carriers. The secondary consequences of efforts to eliminate host-restricted Salmonella serovars demonstrate that basic ecological principles govern the environmental niches occupied by these pathogens, making it impossible to thwart Salmonella infections without a clear understanding of the human, animal, and environmental reservoirs of these pathogens. Thus, transmission of S. enterica provides a compelling example of the One Health paradigm because reducing human infections will require the reduction of Salmonella in animals and limitation of transmission from the environment.

  14. Carbonate petroleum reservoirs

    SciTech Connect

    Roehl, P.O.; Choquette, P.W.

    1985-01-01

    This book presents papers on the geology of petroleum deposits. Topics considered include diagenesis, porosity, dolomite reservoirs, deposition, reservoir rock, reefs, morphology, fracture-controlled production, Cenozoic reservoirs, Mesozoic reservoirs, and Paleozoic reservoirs.

  15. Animal Reservoir, Natural and Socioeconomic Variations and the Transmission of Hemorrhagic Fever with Renal Syndrome in Chenzhou, China, 2006–2010

    PubMed Central

    Basta, Nicole; Cazelles, Bernard; Li, Xiu-Jun; Lin, Xiao-Ling; Wu, Hong-Wei; Chen, Bi-Yun; Yang, Hui-Suo; Xu, Bing; Grenfell, Bryan

    2014-01-01

    Background China has the highest incidence of hemorrhagic fever with renal syndrome (HFRS) worldwide. Reported cases account for 90% of the total number of global cases. By 2010, approximately 1.4 million HFRS cases had been reported in China. This study aimed to explore the effect of the rodent reservoir, and natural and socioeconomic variables, on the transmission pattern of HFRS. Methodology/Principal Findings Data on monthly HFRS cases were collected from 2006 to 2010. Dynamic rodent monitoring data, normalized difference vegetation index (NDVI) data, climate data, and socioeconomic data were also obtained. Principal component analysis was performed, and the time-lag relationships between the extracted principal components and HFRS cases were analyzed. Polynomial distributed lag (PDL) models were used to fit and forecast HFRS transmission. Four principal components were extracted. Component 1 (F1) represented rodent density, the NDVI, and monthly average temperature. Component 2 (F2) represented monthly average rainfall and monthly average relative humidity. Component 3 (F3) represented rodent density and monthly average relative humidity. The last component (F4) represented gross domestic product and the urbanization rate. F2, F3, and F4 were significantly correlated, with the monthly HFRS incidence with lags of 4 months (r = −0.289, P<0.05), 5 months (r = −0.523, P<0.001), and 0 months (r = −0.376, P<0.01), respectively. F1 was correlated with the monthly HFRS incidence, with a lag of 4 months (r = 0.179, P = 0.192). Multivariate PDL modeling revealed that the four principal components were significantly associated with the transmission of HFRS. Conclusions The monthly trend in HFRS cases was significantly associated with the local rodent reservoir, climatic factors, the NDVI, and socioeconomic conditions present during the previous months. The findings of this study may facilitate the development of early warning systems for the

  16. Survey of Wild Mammal Hosts of Cutaneous Leishmaniasis Parasites in Panamá and Costa Rica

    PubMed Central

    González, Kadir; Calzada, José E.; Saldaña, Azael; Rigg, Chystrie A.; Alvarado, Gilbert; Rodríguez-Herrera, Bernal; Kitron, Uriel D.; Adler, Gregory H.; Gottdenker, Nicole L.; Chaves, Luis Fernando; Baldi, Mario

    2015-01-01

    The eco-epidemiology of American cutaneous leishmaniasis (ACL) is driven by animal reservoir species that are a source of infection for sand flies that serve as vectors infecting humans with Leishmania spp parasites. The emergence and re-emergence of this disease across Latin America calls for further studies to identify reservoir species associated with enzootic transmission. Here, we present results from a survey of 52 individuals from 13 wild mammal species at endemic sites in Costa Rica and Panama where ACL mammal hosts have not been previously studied. For Leishmania spp. diagnostics we employed a novel PCR technique using blood samples collected on filter paper. We only found Leishmania spp parasites in one host, the two-toed sloth, Choloepus hoffmanni. Our findings add further support to the role of two-toed sloths as an important ACL reservoir in Central America. PMID:25859156

  17. Survey of wild mammal hosts of cutaneous leishmaniasis parasites in panamá and costa rica.

    PubMed

    González, Kadir; Calzada, José E; Saldaña, Azael; Rigg, Chystrie A; Alvarado, Gilbert; Rodríguez-Herrera, Bernal; Kitron, Uriel D; Adler, Gregory H; Gottdenker, Nicole L; Chaves, Luis Fernando; Baldi, Mario

    2015-03-01

    The eco-epidemiology of American cutaneous leishmaniasis (ACL) is driven by animal reservoir species that are a source of infection for sand flies that serve as vectors infecting humans with Leishmania spp parasites. The emergence and re-emergence of this disease across Latin America calls for further studies to identify reservoir species associated with enzootic transmission. Here, we present results from a survey of 52 individuals from 13 wild mammal species at endemic sites in Costa Rica and Panama where ACL mammal hosts have not been previously studied. For Leishmania spp. diagnostics we employed a novel PCR technique using blood samples collected on filter paper. We only found Leishmania spp parasites in one host, the two-toed sloth, Choloepus hoffmanni. Our findings add further support to the role of two-toed sloths as an important ACL reservoir in Central America.

  18. Non-avian animal reservoirs present a source of influenza A PB1-F2 proteins with novel virulence-enhancing markers.

    PubMed

    Alymova, Irina V; York, Ian A; McCullers, Jonathan A

    2014-01-01

    PB1-F2 protein, expressed from an alternative reading frame of most influenza A virus (IAV) PB1 segments, may possess specific residues associated with enhanced inflammation (L62, R75, R79, and L82) and cytotoxicity (I68, L69, and V70). These residues were shown to increase the pathogenicity of primary viral and secondary bacterial infections in a mouse model. In contrast to human seasonal influenza strains, virulence-associated residues are present in PB1-F2 proteins from pandemic H1N1 1918, H2N2 1957, and H3N2 1968, and highly pathogenic H5N1 strains, suggesting their contribution to viruses' pathogenic phenotypes. Non-human influenza strains may act as donors of virulent PB1-F2 proteins. Previously, avian influenza strains were identified as a potential source of inflammatory, but not cytotoxic, PB1-F2 residues. Here, we analyze the frequency of virulence-associated residues in PB1-F2 sequences from IAVs circulating in mammalian species in close contact with humans: pigs, horses, and dogs. All four inflammatory residues were found in PB1-F2 proteins from these viruses. Among cytotoxic residues, I68 was the most common and was especially prevalent in equine and canine IAVs. Historically, PB1-F2 from equine (about 75%) and canine (about 20%) IAVs were most likely to have combinations of the highest numbers of residues associated with inflammation and cytotoxicity, compared to about 7% of swine IAVs. Our analyses show that, in addition to birds, pigs, horses, and dogs are potentially important sources of pathogenic PB1-F2 variants. There is a need for surveillance of IAVs with genetic markers of virulence that may be emerging from these reservoirs in order to improve pandemic preparedness and response.

  19. Molecular insights into farm animal and zoonotic Salmonella infections

    PubMed Central

    Stevens, Mark P.; Humphrey, Tom J.; Maskell, Duncan J.

    2009-01-01

    Salmonella enterica is a facultative intracellular pathogen of worldwide importance. Infections may present in a variety of ways, from asymptomatic colonization to inflammatory diarrhoea or typhoid fever depending on serovar- and host-specific factors. Human diarrhoeal infections are frequently acquired via the food chain and farm environment by virtue of the ability of selected non-typhoidal serovars to colonize the intestines of food-producing animals and contaminate the avian reproductive tract and egg. Colonization of reservoir hosts often occurs in the absence of clinical symptoms; however, some S. enterica serovars threaten animal health owing to their ability to cause acute enteritis or translocate from the intestines to other organs causing fever, septicaemia and abortion. Despite the availability of complete genome sequences of isolates representing several serovars, the molecular mechanisms underlying Salmonella colonization, pathogenesis and transmission in reservoir hosts remain ill-defined. Here we review current knowledge of the bacterial factors influencing colonization of food-producing animals by Salmonella and the basis of host range, differential virulence and zoonotic potential. PMID:19687040

  20. On a model simulating lack of hydraulic connection between a man-made reservoir and the volume of poroelastic rock hosting the focus of a post-impoundment earthquake

    NASA Astrophysics Data System (ADS)

    Chander, Ramesh; Tomar, S. K.

    2016-12-01

    The idea that a direct hydraulic connection between a man-made reservoir and the foci of post-impoundment earthquakes may not exist at all sites is eminently credible on geological grounds. Our aim is to provide a simple earth model and related theory for use during investigations of earthquakes near new man-made reservoirs. We consider a uniform circular reservoir which rests on the top surface of a no-hydraulic-connection earth model (NHCEM). The model comprises a top elastic (E) layer, an intermediate poroelastic (P) layer, and a bottom elastic half space. The focus of a potential earthquake in the P layer is located directly under the reservoir. The E layer disrupts the hydraulic connection between the reservoir and the focus. Depth of water in the reservoir varies as H ' + hcos( ω t). Expressions for reservoir-induced stresses and pore pressure in different layers of the NHCEM are obtained by solving the boundary-value problem invoking full coupling between mean normal stress and pore pressure in the P layer. As an application of the derived mathematical results, we have examined and found that earthquakes on 60∘ normal faults may occur in the P-layer of a selected NHCEM at epochs of low reservoir level if the reservoir lies mostly in the footwall of the fault. The exercise was motivated by observations of such earthquakes under the man-made Lake Mead after it was impounded.

  1. New kind of polarotaxis governed by degree of polarization: attraction of tabanid flies to differently polarizing host animals and water surfaces

    NASA Astrophysics Data System (ADS)

    Egri, Ádám; Blahó, Miklós; Sándor, András; Kriska, György; Gyurkovszky, Mónika; Farkas, Róbert; Horváth, Gábor

    2012-05-01

    Aquatic insects find their habitat from a remote distance by means of horizontal polarization of light reflected from the water surface. This kind of positive polarotaxis is governed by the horizontal direction of polarization (E-vector). Tabanid flies also detect water by this kind of polarotaxis. The host choice of blood-sucking female tabanids is partly governed by the linear polarization of light reflected from the host's coat. Since the coat-reflected light is not always horizontally polarized, host finding by female tabanids may be different from the established horizontal E-vector polarotaxis. To reveal the optical cue of the former polarotaxis, we performed choice experiments in the field with tabanid flies using aerial and ground-based visual targets with different degrees and directions of polarization. We observed a new kind of polarotaxis being governed by the degree of polarization rather than the E-vector direction of reflected light. We show here that female and male tabanids use polarotaxis governed by the horizontal E-vector to find water, while polarotaxis based on the degree of polarization serves host finding by female tabanids. As a practical by-product of our studies, we explain the enigmatic attractiveness of shiny black spheres used in canopy traps to catch tabanids.

  2. Aposymbiotic culture of the sepiolid squid Euprymna scolopes: role of the symbiotic bacterium Vibrio fischeri in host animal growth, development, and light organ morphogenesis.

    PubMed

    Claes, M F; Dunlap, P V

    2000-02-15

    The sepiolid squid Euprymna scolopes forms a bioluminescent mutualism with the luminous bacterium Vibrio fischeri, harboring V. fischeri cells in a complex ventral light organ and using the bacterial light in predator avoidance. To characterize the contribution of V. fischeri to the growth and development of E. scolopes and to define the long-term effects of bacterial colonization on light organ morphogenesis, we developed a mariculture system for the culture of E. scolopes from hatching to adulthood, employing artificial seawater, lighting that mimicked that of the natural environment, and provision of prey sized to match the developmental stage of E. scolopes. Animals colonized by V. fischeri and animals cultured in the absence of V. fischeri (aposymbiotic) grew and survived equally well, developed similarly, and reached sexual maturity at a similar age. Development of the light organ accessory tissues (lens, reflectors, and ink sac) was similar in colonized and aposymbiotic animals with no obvious morphometric or histological differences. Colonization by V. fischeri influenced regression of the ciliated epithelial appendages (CEAs), the long-term growth of the light organ epithelial tubules, and the appearance of the cells composing the ciliated ducts, which exhibit characteristics of secretory tissue. In certain cases, aposymbiotic animals retained the CEAs in a partially regressed state and remained competent to initiate symbiosis with V. fischeri into adulthood. In other cases, the CEAs regressed fully in aposymbiotic animals, and these animals were not colonizable. The results demonstrate that V. fischeri is not required for normal growth and development of the animal or for development of the accessory light organ tissues and that morphogenesis of only those tissues coming in contact with the bacteria (CEAs, ciliated ducts, and light organ epithelium) is altered by bacterial colonization of the light organ. Therefore, V. fischeri apparently makes no major

  3. Chlamydia pneumoniae Is Genetically Diverse in Animals and Appears to Have Crossed the Host Barrier to Humans on (At Least) Two Occasions

    PubMed Central

    Mitchell, Candice M.; Hutton, Susan; Myers, Garry S. A.; Brunham, Robert; Timms, Peter

    2010-01-01

    Chlamydia pneumoniae is a common human and animal pathogen associated with a wide range of diseases. Since the first isolation of C. pneumoniae TWAR in 1965, all human isolates have been essentially clonal, providing little evolutionary insight. To address this gap, we investigated the genetic diversity of 30 isolates from diverse geographical locations, from both human and animal origin (amphibian, reptilian, equine and marsupial). Based on the level of variation that we observed at 23 discreet gene loci, it was clearly evident that the animal isolates were more diverse than the isolates of human origin. Furthermore, we show that C. pneumoniae isolates could be grouped into five major genotypes, A-E, with A, B, D and E genotypes linked by geographical location, whereas genotype C was found across multiple continents. Our evidence strongly supports two separate animal-to-human cross species transfer events in the evolutionary history of this pathogen. The C. pneumoniae human genotype identified in the USA, Canada, Taiwan, Iran, Japan, Korea and Australia (non-Indigenous) most likely originated from a single amphibian or reptilian lineage, which appears to have been previously geographically widespread. We identified a separate human lineage present in two Australian Indigenous isolates (independent geographical locations). This lineage is distinct and is present in Australian amphibians as well as a range of Australian marsupials. PMID:20502684

  4. Whole Genome Sequencing demonstrates that Geographic Variation of Escherichia coli O157 Genotypes Dominates Host Association

    PubMed Central

    Strachan, Norval J. C.; Rotariu, Ovidiu; Lopes, Bruno; MacRae, Marion; Fairley, Susan; Laing, Chad; Gannon, Victor; Allison, Lesley J.; Hanson, Mary F.; Dallman, Tim; Ashton, Philip; Franz, Eelco; van Hoek, Angela H. A. M.; French, Nigel P.; George, Tessy; Biggs, Patrick J.; Forbes, Ken J.

    2015-01-01

    Genetic variation in an infectious disease pathogen can be driven by ecological niche dissimilarities arising from different host species and different geographical locations. Whole genome sequencing was used to compare E. coli O157 isolates from host reservoirs (cattle and sheep) from Scotland and to compare genetic variation of isolates (human, animal, environmental/food) obtained from Scotland, New Zealand, Netherlands, Canada and the USA. Nei’s genetic distance calculated from core genome single nucleotide polymorphisms (SNPs) demonstrated that the animal isolates were from the same population. Investigation of the Shiga toxin bacteriophage and their insertion sites (SBI typing) revealed that cattle and sheep isolates had statistically indistinguishable rarefaction profiles, diversity and genotypes. In contrast, isolates from different countries exhibited significant differences in Nei’s genetic distance and SBI typing. Hence, after successful international transmission, which has occurred on multiple occasions, local genetic variation occurs, resulting in a global patchwork of continental and trans-continental phylogeographic clades. These findings are important for three reasons: first, understanding transmission and evolution of infectious diseases associated with multiple host reservoirs and multi-geographic locations; second, highlighting the relevance of the sheep reservoir when considering farm based interventions; and third, improving our understanding of why human disease incidence varies across the world. PMID:26442781

  5. Whole Genome Sequencing demonstrates that Geographic Variation of Escherichia coli O157 Genotypes Dominates Host Association.

    PubMed

    Strachan, Norval J C; Rotariu, Ovidiu; Lopes, Bruno; MacRae, Marion; Fairley, Susan; Laing, Chad; Gannon, Victor; Allison, Lesley J; Hanson, Mary F; Dallman, Tim; Ashton, Philip; Franz, Eelco; van Hoek, Angela H A M; French, Nigel P; George, Tessy; Biggs, Patrick J; Forbes, Ken J

    2015-10-07

    Genetic variation in an infectious disease pathogen can be driven by ecological niche dissimilarities arising from different host species and different geographical locations. Whole genome sequencing was used to compare E. coli O157 isolates from host reservoirs (cattle and sheep) from Scotland and to compare genetic variation of isolates (human, animal, environmental/food) obtained from Scotland, New Zealand, Netherlands, Canada and the USA. Nei's genetic distance calculated from core genome single nucleotide polymorphisms (SNPs) demonstrated that the animal isolates were from the same population. Investigation of the Shiga toxin bacteriophage and their insertion sites (SBI typing) revealed that cattle and sheep isolates had statistically indistinguishable rarefaction profiles, diversity and genotypes. In contrast, isolates from different countries exhibited significant differences in Nei's genetic distance and SBI typing. Hence, after successful international transmission, which has occurred on multiple occasions, local genetic variation occurs, resulting in a global patchwork of continental and trans-continental phylogeographic clades. These findings are important for three reasons: first, understanding transmission and evolution of infectious diseases associated with multiple host reservoirs and multi-geographic locations; second, highlighting the relevance of the sheep reservoir when considering farm based interventions; and third, improving our understanding of why human disease incidence varies across the world.

  6. Extensive host sharing of central European Tula virus.

    PubMed

    Schmidt-Chanasit, Jonas; Essbauer, Sandra; Petraityte, Rasa; Yoshimatsu, Kumiko; Tackmann, Kirsten; Conraths, Franz J; Sasnauskas, Kestutis; Arikawa, Jiro; Thomas, Astrid; Pfeffer, Martin; Scharninghausen, Jerrold J; Splettstoesser, Wolf; Wenk, Matthias; Heckel, Gerald; Ulrich, Rainer G

    2010-01-01

    To examine the host association of Tula virus (TULV), a hantavirus present in large parts of Europe, we investigated a total of 791 rodents representing 469 Microtus arvalis and 322 Microtus agrestis animals from northeast, northwest, and southeast Germany, including geographical regions with sympatric occurrence of both vole species, for the presence of TULV infections. Based on serological investigation, reverse transcriptase PCR, and subsequent sequence analysis of partial small (S) and medium (M) segments, we herein show that TULV is carried not only by its commonly known host M. arvalis but also frequently by M. agrestis in different regions of Germany for a prolonged time period. At one trapping site, TULV was exclusively detected in M. agrestis, suggesting an isolated transmission cycle in this rodent reservoir separate from spillover infections of TULV-carrying M. arvalis. Phylogenetic analysis of the S and M segment sequences demonstrated geographical clustering of the TULV sequences irrespective of the host, M. arvalis or M. agrestis. The novel TULV lineages from northeast, northwest, and southeast Germany described here are clearly separated from each other and from other German, European, or Asian lineages, suggesting their stable geographical localization and fast sequence evolution. In conclusion, these results demonstrate that TULV represents a promiscuous hantavirus with a large panel of susceptible hosts. In addition, this may suggest an alternative evolution mode, other than a strict coevolution, for this virus in its Microtus hosts, which should be proven in further large-scale investigations on sympatric Microtus hosts.

  7. Rodent reservoirs of future zoonotic diseases.

    PubMed

    Han, Barbara A; Schmidt, John Paul; Bowden, Sarah E; Drake, John M

    2015-06-02

    The increasing frequency of zoonotic disease events underscores a need to develop forecasting tools toward a more preemptive approach to outbreak investigation. We apply machine learning to data describing the traits and zoonotic pathogen diversity of the most speciose group of mammals, the rodents, which also comprise a disproportionate number of zoonotic disease reservoirs. Our models predict reservoir status in this group with over 90% accuracy, identifying species with high probabilities of harboring undiscovered zoonotic pathogens based on trait profiles that may serve as rules of thumb to distinguish reservoirs from nonreservoir species. Key predictors of zoonotic reservoirs include biogeographical properties, such as range size, as well as intrinsic host traits associated with lifetime reproductive output. Predicted hotspots of novel rodent reservoir diversity occur in the Middle East and Central Asia and the Midwestern United States.

  8. Hepacivirus NS3/4A Proteases Interfere with MAVS Signaling in both Their Cognate Animal Hosts and Humans: Implications for Zoonotic Transmission.

    PubMed

    Anggakusuma; Brown, Richard J P; Banda, Dominic H; Todt, Daniel; Vieyres, Gabrielle; Steinmann, Eike; Pietschmann, Thomas

    2016-12-01

    Multiple novel members of the genus Hepacivirus have recently been discovered in diverse mammalian species. However, to date, their replication mechanisms and zoonotic potential have not been explored in detail. The NS3/4A serine protease of hepatitis C virus (HCV) is critical for cleavage of the viral polyprotein. It also cleaves the cellular innate immune adaptor MAVS, thus decreasing interferon (IFN) production and contributing to HCV persistence in the human host. To investigate the conservation of fundamental aspects of the hepaciviral life cycle, we explored if MAVS cleavage and suppression of innate immune signaling represent a common mechanism employed across different clades of the genus Hepacivirus to enhance viral replication. To estimate the zoonotic potential of these nonhuman hepaciviruses, we assessed if their NS3/4A proteases were capable of cleaving human MAVS. NS3/4A proteases of viruses infecting colobus monkeys, rodents, horses, and cows cleaved the MAVS proteins of their cognate hosts and interfered with the ability of MAVS to induce the IFN-β promoter. All NS3/4A proteases from nonhuman viruses readily cleaved human MAVS. Thus, NS3/4A-dependent cleavage of MAVS is a conserved replication strategy across multiple clades within the genus Hepacivirus Human MAVS is susceptible to cleavage by these nonhuman viral proteases, indicating that it does not pose a barrier for zoonotic transmission of these viruses to humans.

  9. Flexible Animation Computer Program

    NASA Technical Reports Server (NTRS)

    Stallcup, Scott S.

    1990-01-01

    FLEXAN (Flexible Animation), computer program animating structural dynamics on Evans and Sutherland PS300-series graphics workstation with VAX/VMS host computer. Typical application is animation of spacecraft undergoing structural stresses caused by thermal and vibrational effects. Displays distortions in shape of spacecraft. Program displays single natural mode of vibration, mode history, or any general deformation of flexible structure. Written in FORTRAN 77.

  10. Transmission or Within-Host Dynamics Driving Pulses of Zoonotic Viruses in Reservoir–Host Populations

    PubMed Central

    Plowright, Raina K.; Peel, Alison J.; Streicker, Daniel G.; Gilbert, Amy T.; McCallum, Hamish; Wood, James; Baker, Michelle L.; Restif, Olivier

    2016-01-01

    Progress in combatting zoonoses that emerge from wildlife is often constrained by limited knowledge of the biology of pathogens within reservoir hosts. We focus on the host–pathogen dynamics of four emerging viruses associated with bats: Hendra, Nipah, Ebola, and Marburg viruses. Spillover of bat infections to humans and domestic animals often coincides with pulses of viral excretion within bat populations, but the mechanisms driving such pulses are unclear. Three hypotheses dominate current research on these emerging bat infections. First, pulses of viral excretion could reflect seasonal epidemic cycles driven by natural variations in population densities and contact rates among hosts. If lifelong immunity follows recovery, viruses may disappear locally but persist globally through migration; in either case, new outbreaks occur once births replenish the susceptible pool. Second, epidemic cycles could be the result of waning immunity within bats, allowing local circulation of viruses through oscillating herd immunity. Third, pulses could be generated by episodic shedding from persistently infected bats through a combination of physiological and ecological factors. The three scenarios can yield similar patterns in epidemiological surveys, but strategies to predict or manage spillover risk resulting from each scenario will be different. We outline an agenda for research on viruses emerging from bats that would allow for differentiation among the scenarios and inform development of evidence-based interventions to limit threats to human and animal health. These concepts and methods are applicable to a wide range of pathogens that affect humans, domestic animals, and wildlife. PMID:27489944

  11. Environmentally transmitted parasites: Host-jumping in a heterogeneous environment.

    PubMed

    Caraco, Thomas; Cizauskas, Carrie A; Wang, Ing-Nang

    2016-05-21

    Groups of chronically infected reservoir-hosts contaminate resource patches by shedding a parasite׳s free-living stage. Novel-host groups visit the same patches, where they are exposed to infection. We treat arrival at patches, levels of parasite deposition, and infection of the novel host as stochastic processes, and derive the expected time elapsing until a host-jump (initial infection of a novel host) occurs. At stationarity, mean parasite densities are independent of reservoir-host group size. But within-patch parasite-density variances increase with reservoir group size. The probability of infecting a novel host declines with parasite-density variance; consequently larger reservoir groups extend the mean waiting time for host-jumping. Larger novel-host groups increase the probability of a host-jump during any single patch visit, but also reduce the total number of visits per unit time. Interaction of these effects implies that the waiting time for the first infection increases with the novel-host group size. If the reservoir-host uses resource patches in any non-uniform manner, reduced spatial overlap between host species increases the waiting time for host-jumping.

  12. Sarcocystosis of animals and humans

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Species of Sarcocystosis, single-celled protozoan parasites in the Phylum Apicomplexa, are widespread in warm-blooded animals. Completion of the life cycle requires two host species: an intermediate (or prey) host and a definitive (or predator) host. Hosts can harbor more than one species of Sarcocy...

  13. Acquired antibiotic resistance among wild animals: the case of Iberian Lynx (Lynx pardinus).

    PubMed

    Sousa, Margarida; Gonçalves, Alexandre; Silva, Nuno; Serra, Rodrigo; Alcaide, Eva; Zorrilla, Irene; Torres, Carmen; Caniça, Manuela; Igrejas, Gilberto; Poeta, Patrícia

    2014-01-01

    The selective pressure generated by the clinical misuse of antibiotics has been the major driving force leading to the emergence of antibiotic resistance among bacteria. Antibiotics or even resistant bacteria are released into the environment and contaminate the surrounding areas. Human and animal populations in contact with these sources are able to become reservoirs of these resistant organisms. Then, due to the convergence between habitats, the contact of wild animals with other animals, humans, or human sources is now more common and this leads to an increase in the exchange of resistance determinants between their microbiota. Indeed, it seems that wildlife populations living in closer proximity to humans have higher levels of antibiotic resistance. Now, the Iberian Lynx (Lynx pardinus) is a part of this issue, being suggested as natural reservoir of acquired resistant bacteria. The emerging public health concern regarding microbial resistance to antibiotics is becoming true: the bacteria are evolving and are now affecting unintentional hosts.

  14. Animal papillomaviruses.

    PubMed

    Rector, Annabel; Van Ranst, Marc

    2013-10-01

    We provide an overview of the host range, taxonomic classification and genomic diversity of animal papillomaviruses. The complete genomes of 112 non-human papillomavirus types, recovered from 54 different host species, are currently available in GenBank. The recent characterizations of reptilian papillomaviruses extend the host range of the Papillomaviridae to include all amniotes. Although the genetically diverse papillomaviruses have a highly conserved genomic lay-out, deviations from this prototypic genome organization are observed in several animal papillomaviruses, and only the core ORFs E1, E2, L2 and L1 are present in all characterized papillomavirus genomes. The discovery of papilloma-polyoma hybrids BPCV1 and BPCV2, containing a papillomaviral late region but an early region encoding typical polyomaviral nonstructural proteins, and the detection of recombination breakpoints between the early and late coding regions of cetacean papillomaviruses, could indicate that early and late gene cassettes of papillomaviruses are relatively independent entities that can be interchanged by recombination.

  15. Modeling the ecologic niche of plague in sylvan and domestic animal hosts to delineate sources of human exposure in the western United States

    PubMed Central

    Haseeb, MA

    2015-01-01

    Plague has been established in the western United States (US) since 1900 following the West Coast introduction of commensal rodents infected with Yersinia pestis via early industrial shipping. Over the last century, plague ecology has transitioned through cycles of widespread human transmission, urban domestic transmission among commensal rodents, and ultimately settled into the predominantly sylvan foci that remain today where it is maintained alternatively by enzootic and epizootic transmission. While zoonotic transmission to humans is much less common in modern times, significant plague risk remains in parts of the western US. Moreover, risk to some threatened species that are part of the epizootic cycle can be quite substantive. This investigation attempted to predict the risk of plague across the western US by modeling the ecologic niche of plague in sylvan and domestic animals identified between 2000 and 2015. A Maxent machine learning algorithm was used to predict this niche based on climate, altitude, land cover, and the presence of an important enzootic species, Peromyscus maniculatus. This model demonstrated good predictive ability (AUC = 86%) and identified areas of high risk in central Colorado, north-central New Mexico, and southwestern and northeastern California. The presence of P. maniculatus, altitude, precipitation during the driest and wettest quarters, and distance to artificial surfaces, all contributed substantively to maximizing the gain function. These findings add to the known landscape epidemiology and infection ecology of plague in the western US and may suggest locations of particular risk to be targeted for wild and domestic animal intervention. PMID:26713244

  16. The Leeuwenhoek Lecture 2001. Animal origins of human infectious disease.

    PubMed

    Weiss, R A

    2001-06-29

    Since time immemorial animals have been a major source of human infectious disease. Certain infections like rabies are recognized as zoonoses caused in each case by direct animal-to-human transmission. Others like measles became independently sustained with the human population so that the causative virus has diverged from its animal progenitor. Recent examples of direct zoonoses are variant Creutzfeldt-Jakob disease arising from bovine spongiform encephalopathy, and the H5N1 avian influenza outbreak in Hong Kong. Epidemics of recent animal origin are the 1918-1919 influenza pandemic, and acquired immune deficiency syndrome caused by human immunodeficiency virus (HIV). Some retroviruses jump into and out of the chromosomal DNA of the host germline, so that they oscillate between being inherited Mendelian traits or infectious agents in different species. Will new procedures like animal-to-human transplants unleash further infections? Do microbes become more virulent upon cross-species transfer? Are animal microbes a threat as biological weapons? Will the vast reservoir of immunodeficient hosts due to the HIV pandemic provide conditions permissive for sporadic zoonoses to take off as human-to-human transmissible diseases? Do human infections now pose a threat to endangered primates? These questions are addressed in this lecture.

  17. Comparative Proteomics Identifies Host Immune System Proteins Affected by Infection with Mycobacterium bovis.

    PubMed

    López, Vladimir; Villar, Margarita; Queirós, João; Vicente, Joaquín; Mateos-Hernández, Lourdes; Díez-Delgado, Iratxe; Contreras, Marinela; Alves, Paulo C; Alberdi, Pilar; Gortázar, Christian; de la Fuente, José

    2016-03-01

    Mycobacteria of the Mycobacterium tuberculosis complex (MTBC) greatly impact human and animal health worldwide. The mycobacterial life cycle is complex, and the mechanisms resulting in pathogen infection and survival in host cells are not fully understood. Eurasian wild boar (Sus scrofa) are natural reservoir hosts for MTBC and a model for mycobacterial infection and tuberculosis (TB). In the wild boar TB model, mycobacterial infection affects the expression of innate and adaptive immune response genes in mandibular lymph nodes and oropharyngeal tonsils, and biomarkers have been proposed as correlates with resistance to natural infection. However, the mechanisms used by mycobacteria to manipulate host immune response are not fully characterized. Our hypothesis is that the immune system proteins under-represented in infected animals, when compared to uninfected controls, are used by mycobacteria to guarantee pathogen infection and transmission. To address this hypothesis, a comparative proteomics approach was used to compare host response between uninfected (TB-) and M. bovis-infected young (TB+) and adult animals with different infection status [TB lesions localized in the head (TB+) or affecting multiple organs (TB++)]. The results identified host immune system proteins that play an important role in host response to mycobacteria. Calcium binding protein A9, Heme peroxidase, Lactotransferrin, Cathelicidin and Peptidoglycan-recognition protein were under-represented in TB+ animals when compared to uninfected TB- controls, but protein levels were higher as infection progressed in TB++ animals when compared to TB- and/or TB+ adult wild boar. MHCI was the only protein over-represented in TB+ adult wild boar when compared to uninfected TB- controls. The results reported here suggest that M. bovis manipulates host immune response by reducing the production of immune system proteins. However, as infection progresses, wild boar immune response recovers to limit pathogen

  18. Comparative Proteomics Identifies Host Immune System Proteins Affected by Infection with Mycobacterium bovis

    PubMed Central

    López, Vladimir; Villar, Margarita; Queirós, João; Vicente, Joaquín; Mateos-Hernández, Lourdes; Díez-Delgado, Iratxe; Contreras, Marinela; Alves, Paulo C.; Alberdi, Pilar; Gortázar, Christian; de la Fuente, José

    2016-01-01

    Mycobacteria of the Mycobacterium tuberculosis complex (MTBC) greatly impact human and animal health worldwide. The mycobacterial life cycle is complex, and the mechanisms resulting in pathogen infection and survival in host cells are not fully understood. Eurasian wild boar (Sus scrofa) are natural reservoir hosts for MTBC and a model for mycobacterial infection and tuberculosis (TB). In the wild boar TB model, mycobacterial infection affects the expression of innate and adaptive immune response genes in mandibular lymph nodes and oropharyngeal tonsils, and biomarkers have been proposed as correlates with resistance to natural infection. However, the mechanisms used by mycobacteria to manipulate host immune response are not fully characterized. Our hypothesis is that the immune system proteins under-represented in infected animals, when compared to uninfected controls, are used by mycobacteria to guarantee pathogen infection and transmission. To address this hypothesis, a comparative proteomics approach was used to compare host response between uninfected (TB-) and M. bovis-infected young (TB+) and adult animals with different infection status [TB lesions localized in the head (TB+) or affecting multiple organs (TB++)]. The results identified host immune system proteins that play an important role in host response to mycobacteria. Calcium binding protein A9, Heme peroxidase, Lactotransferrin, Cathelicidin and Peptidoglycan-recognition protein were under-represented in TB+ animals when compared to uninfected TB- controls, but protein levels were higher as infection progressed in TB++ animals when compared to TB- and/or TB+ adult wild boar. MHCI was the only protein over-represented in TB+ adult wild boar when compared to uninfected TB- controls. The results reported here suggest that M. bovis manipulates host immune response by reducing the production of immune system proteins. However, as infection progresses, wild boar immune response recovers to limit pathogen

  19. Beyond Rabies: Are Free-Ranging Skunks (Mephitis mephitis) in British Columbia Reservoirs of Emerging Infection?

    PubMed

    Britton, A P; Redford, T; Bidulka, J J; Scouras, A P; Sojonky, K R; Zabek, E; Schwantje, H; Joseph, T

    2017-04-01

    Wild animal reservoirs are an important source of emerging and zoonotic infection. Skunks (Mephitis mephitis) are a reservoir of skunk strain rabies virus in Canada, with the exception of some areas including the province of British Columbia (BC). Beyond rabies, the reservoir status of skunks for emerging and zoonotic pathogens in BC is unknown. From March 2011 to February 2015, 50 free-ranging skunks were necropsied and tested for 4 pathogens: influenza A, Aleutian disease virus (ADV), Leptospira spp. and Salmonella spp. Two skunks (4%) with respiratory disease caused by influenza A (H1N1) pdm09 were detected during the human flu season suggesting that skunks may represent a target population for reverse zoonosis of this strain of influenza A virus. High prevalence of ADV infection was detected (43/50, 86%). Two of the infected skunks exhibited Aleutian disease (AD) suggesting that skunks act as both a reservoir and a target population for the virus. Most studies of ADV have focused on the potential for infection of free-ranging species living near mink farms. Our study suggests that urban skunks may be a primary host for the virus independent of domestic mink. Whether skunks act as a reservoir of ADV infection for other peridomestic species will depend on host specificity of the viral strains. Leptospira interrogans was detected in 18% (9/49) of the skunks. Identification of the serovar(s) detected is needed to determine any public health risk of leptospirosis following exposure to infected skunks. Salmonella spp. was isolated from three of 43 skunks (7%), specifically S. Typhimurium, S. Muenchen and S. Enteritidis. These serotypes cause disease in humans, but the low prevalence of infection suggests there is a low risk for zoonotic transmission.

  20. Bats prove to be rich reservoirs for emerging viruses

    USGS Publications Warehouse

    Calisher, Charles H.; Holmes, Kathryn V.; Dominguez, Samuel R.; Schountz, Tony; Cryan, Paul M.

    2008-01-01

    Emerging pathogens, many of them viruses, continue to surprise us, providing many newly recognized diseases to study and to try to control. Many of these emergent viruses are zoonotic, transmitted from reservoirs in wild or domestic animals to humans, either by insect vectors or by exposure to the droppings or tissues of such animals. One rich- but, until recently, underappreciated-source of emergent viruses is bats (Chiroptera, meaning "hand wing"). Accounting for 1,116, or nearly one fourth, of the 4,600 recognized species of mammals, bats are grouped into two suborders Megachiroptera, which contains a single family, Pteropodidae, consisting of 42 genera and 186 species, and Microchiroptera, which contains 17 families, 160 genera, and 930 species. Although bats are among the most abundant, diverse, and geographically dispersed orders of terrestrial mammals, research on these flying mammals historically focused more on their habits and outward characteristics than on their role in carrying microorganisms and transmitting pathogens to other species. Even in those cases where bats were known to carry particular pathogens, the microbiologists who studied those pathogens typically knew little about the bat hosts. Hence, investigators now are seeking to explain how variations of anatomy, physiology, ecology, and behavior influence the roles of bats as hosts for viral pathogens.

  1. Status of Norris Reservoir

    SciTech Connect

    Not Available

    1990-09-01

    This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Norris Reservoir summarizes reservoir and watershed characteristics, reservoir uses, conditions that impair reservoir uses, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most up-to-date publications and data available, and from interviews with water resource professionals in various federal, state, and local agencies, and in public and private water supply and wastewater treatment facilities. 14 refs., 3 figs.

  2. Serosurvey study of Toscana virus in domestic animals, Granada, Spain.

    PubMed

    Navarro-Marí, José María; Palop-Borrás, Begoña; Pérez-Ruiz, Mercedes; Sanbonmatsu-Gámez, Sara

    2011-05-01

    Toscana virus (TOSV) is transmitted by infected sandflies. In Mediterranean countries, TOSV is one of the major viral pathogens involved in aseptic meningitis and meningoencephalitis in humans. It remains unclear if there are animal reservoirs able to maintain the virus through the cold months of the year, when the vector is not circulating. From May to October of 2006 and 2007, we conducted a serosurvey study on domestic animals from Granada province (southern Spain). TOSV was investigated in 1186 serum samples from horses, goats, pigs, cats, dogs, sheep, and cows by serology (indirect fluorescence assay), viral culture, and RT-polymerase chain reaction. Specific anti-TOSV antibodies were detected in 429 (36.2%) serum samples. The highest seropositivity rates were observed in cats (59.6%) and dogs (48.3%). These results suggest that an important percentage of the domestic animals have been infected by TOSV. Significantly different seroprevalence rates were detected in goats among distinct geographical areas. All viral cultures were negative. TOSV was detected by RT-polymerase chain reaction in only one serum sample from a goat. Thus, the studied animals do not seem to act as reservoirs for TOSV; otherwise, they could be amplifying hosts for the virus.

  3. Phylogenetic analysis of a newfound bat-borne hantavirus supports a laurasiatherian host association for ancestral mammalian hantaviruses.

    PubMed

    Witkowski, Peter T; Drexler, Jan F; Kallies, René; Ličková, Martina; Bokorová, Silvia; Mananga, Gael D; Szemes, Tomáš; Leroy, Eric M; Krüger, Detlev H; Drosten, Christian; Klempa, Boris

    2016-07-01

    Until recently, hantaviruses (family Bunyaviridae) were believed to originate from rodent reservoirs. However, genetically distinct hantaviruses were lately found in shrews and moles, as well as in bats from Africa and Asia. Bats (order Chiroptera) are considered important reservoir hosts for emerging human pathogens. Here, we report on the identification of a novel hantavirus, provisionally named Makokou virus (MAKV), in Noack's Roundleaf Bat (Hipposideros ruber) in Gabon, Central Africa. Phylogenetic analysis of the genomic l-segment showed that MAKV was the most closely related to other bat-borne hantaviruses and shared a most recent common ancestor with the Asian hantaviruses Xuan Son and Laibin. Breakdown of the virus load in a bat animal showed that MAKV resembles rodent-borne hantaviruses in its organ distribution in that it predominantly occurred in the spleen and kidney; this provides a first insight into the infection pattern of bat-borne hantaviruses. Ancestral state reconstruction based on a tree of l gene sequences of all relevant hantavirus lineages was combined with phylogenetic fossil host hypothesis testing, leading to a statistically significant rejection of the mammalian superorder Euarchontoglires (including rodents) but not the superorder Laurasiatheria (including shrews, moles, and bats) as potential hosts of ancestral hantaviruses at most basal tree nodes. Our data supports the emerging concept of bats as previously overlooked hantavirus reservoir hosts.

  4. Hendra virus and Nipah virus animal vaccines.

    PubMed

    Broder, Christopher C; Weir, Dawn L; Reid, Peter A

    2016-06-24

    Hendra virus (HeV) and Nipah virus (NiV) are zoonotic viruses that emerged in the mid to late 1990s causing disease outbreaks in livestock and people. HeV appeared in Queensland, Australia in 1994 causing a severe respiratory disease in horses along with a human case fatality. NiV emerged a few years later in Malaysia and Singapore in 1998-1999 causing a large outbreak of encephalitis with high mortality in people and also respiratory disease in pigs which served as amplifying hosts. The key pathological elements of HeV and NiV infection in several species of mammals, and also in people, are a severe systemic and often fatal neurologic and/or respiratory disease. In people, both HeV and NiV are also capable of causing relapsed encephalitis following recovery from an acute infection. The known reservoir hosts of HeV and NiV are several species of pteropid fruit bats. Spillovers of HeV into horses continue to occur in Australia and NiV has caused outbreaks in people in Bangladesh and India nearly annually since 2001, making HeV and NiV important transboundary biological threats. NiV in particular possesses several features that underscore its potential as a pandemic threat, including its ability to infect humans directly from natural reservoirs or indirectly from other susceptible animals, along with a capacity of limited human-to-human transmission. Several HeV and NiV animal challenge models have been developed which have facilitated an understanding of pathogenesis and allowed for the successful development of both active and passive immunization countermeasures.

  5. Differential compartmentalization of Streptococcus pyogenes virulence factors and host protein binding properties as a mechanism for host adaptation.

    PubMed

    Kilsgård, Ola; Karlsson, Christofer; Malmström, Erik; Malmström, Johan

    2016-11-01

    Streptococcus pyogenes is an important human pathogen responsible for substantial morbidity and mortality worldwide. Although S. pyogenes is a strictly human pathogen with no other known animal reservoir, several murine infection models exist to explore different aspects of the bacterial pathogenesis. Inoculating mice with wild-type S. pyogenes strains can result in the generation of new bacterial phenotypes that are hypervirulent compared to the original inoculum. In this study, we used a serial mass spectrometry based proteomics strategy to investigate if these hypervirulent strains have an altered distribution of virulence proteins across the intracellular, surface associated and secreted bacterial compartments and if any change in compartmentalization can alter the protein-protein interaction network between bacteria and host proteins. Quantitative analysis of the S. pyogenes surface and secreted proteomes revealed that animal passaged strains are associated with significantly higher amount of virulence factors on the bacterial surface and in the media. This altered virulence factor compartmentalization results in increased binding of several mouse plasma proteins to the bacterial surface, a trend that was consistent for mouse plasma from several different mouse strains. In general, both the wild-type strain and animal passaged strain were capable of binding high amounts of human plasma proteins. However, compared to the non-passaged strains, the animal passaged strains displayed an increased ability to bind mouse plasma proteins, in particular for M protein binders, indicating that the increased affinity for mouse blood plasma proteins is a consequence of host adaptation of this pathogen to a new host. In conclusion, plotting the total amount of virulence factors against the total amount of plasma proteins associated to the bacterial surface could clearly separate out animal passaged strains from wild type strains indicating a virulence model that could

  6. HIV reservoirs: what, where and how to target them.

    PubMed

    Churchill, Melissa J; Deeks, Steven G; Margolis, David M; Siliciano, Robert F; Swanstrom, Ronald

    2016-01-01

    One of the main challenges in the fight against HIV infection is to develop strategies that are able to eliminate the persistent viral reservoir that harbours integrated, replication-competent provirus within host cellular DNA. This reservoir is resistant to antiretroviral therapy (ART) and to clearance by the immune system of the host; viruses originating from this reservoir lead to rebound viraemia once treatment is stopped, giving rise to new rounds of infection. Several studies have focused on elucidating the cells and tissues that harbour persistent virus, the true size of the reservoir and how best to target it, but these topics are the subject of ongoing debate. In this Viewpoint article, several experts in the field discuss the constitution of the viral reservoir, how best to measure it and the best ways to target this source of persistent infection.

  7. Hantavirus immunology of rodent reservoirs: current status and future directions.

    PubMed

    Schountz, Tony; Prescott, Joseph

    2014-03-14

    Hantaviruses are hosted by rodents, insectivores and bats. Several rodent-borne hantaviruses cause two diseases that share many features in humans, hemorrhagic fever with renal syndrome in Eurasia or hantavirus cardiopulmonary syndrome in the Americas. It is thought that the immune response plays a significant contributory role in these diseases. However, in reservoir hosts that have been closely examined, little or no pathology occurs and infection is persistent despite evidence of adaptive immune responses. Because most hantavirus reservoirs are not model organisms, it is difficult to conduct meaningful experiments that might shed light on how the viruses evade sterilizing immune responses and why immunopathology does not occur. Despite these limitations, recent advances in instrumentation and bioinformatics will have a dramatic impact on understanding reservoir host responses to hantaviruses by employing a systems biology approach to identify important pathways that mediate virus/reservoir relationships.

  8. A longitudinal study of an endemic disease in its wildlife reservoir: cowpox and wild rodents.

    PubMed Central

    Hazel, S. M.; Bennett, M.; Chantrey, J.; Bown, K.; Cavanagh, R.; Jones, T. R.; Baxby, D.; Begon, M.

    2000-01-01

    Cowpox is an orthopoxvirus infection endemic in European wild rodents, but with a wide host range including human beings. In this longitudinal study we examined cowpox in two wild rodent species, bank voles Clethrionomys glareolus and wood mice Apodemus sylvaticus, to investigate the dynamics of a virus in its wild reservoir host. Trapping was carried out at 4-weekly intervals over 3 years and each animal caught was uniquely identified, blood sampled and tested for antibodies to cowpox. Antibody prevalence was higher in bank voles than in wood mice and seroconversion varied seasonally, with peaks in autumn. Infection was most common in males of both species but no clear association with age was demonstrated. This study provides a model for studying other zoonotic infections that derive from wild mammals since other approaches, such as one-off samples, will fail to detect the variation in infection and thus, risk to human health, demonstrated here. PMID:10982080

  9. Status of Cherokee Reservoir

    SciTech Connect

    Not Available

    1990-08-01

    This is the first in a series of reports prepared by Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overviews of Cherokee Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports, publications, and data available, and interviews with water resource professionals in various Federal, state, and local agencies and in public and private water supply and wastewater treatment facilities. 11 refs., 4 figs., 1 tab.

  10. Status of Wheeler Reservoir

    SciTech Connect

    Not Available

    1990-09-01

    This is one in a series of status reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Wheeler Reservoir summarizes reservoir purposes and operation, reservoir and watershed characteristics, reservoir uses and use impairments, and water quality and aquatic biological conditions. The information presented here is from the most recent reports, publications, and original data available. If no recent data were available, historical data were summarized. If data were completely lacking, environmental professionals with special knowledge of the resource were interviewed. 12 refs., 2 figs.

  11. West Nile virus reemergence in Romania: a serologic survey in host species.

    PubMed

    Ludu Oslobanu, Elena Luanda; Mihu-Pintilie, Alin; Anită, Dragos; Anita, Adriana; Lecollinet, Sylvie; Savuta, Gheorghe

    2014-05-01

    The presence of West Nile virus (WNV) in humans has been known in Romania since the 1950s; the 1996 epidemics emphasized the reemergence potential of WNV in Romania. Serological surveys made on susceptible species, known as good sentinels or reservoir hosts, e.g., horses, wild and domestic birds were undertaken from 2006-2011. Our results corroborated incidence data in human patients and other recent seroprevalence studies in animals, and should partially clarify the emergence of WNV in the eastern rural territories of Romania. It also highlighted risk zones for endemic WNV infection in Romania.

  12. Dolomite reservoirs: Porosity evolution and reservoir characteristics

    SciTech Connect

    Sun, S.Q.

    1995-02-01

    Systematic analyses of the published record of dolomite reservoirs worldwide reveal that the majority of hydrocarbon-producing dolomite reservoirs occurs in (1) peritidal-dominated carbonate, (2) subtidal carbonate associated with evaporitic tidal flat/lagoon, (3) subtidal carbonate associated with basinal evaporite, and (4) nonevaporitic carbonate sequence associated with topographic high/unconformity, platform-margin buildup or fault/fracture. Reservoir characteristics vary greatly from one dolomite type to another depending upon the original sediment fabric, the mechanism by which dolomite was formed, and the extent to which early formed dolomite was modified by post-dolomitization diagenetic processes (e.g., karstification, fracturing, and burial corrosion). This paper discusses the origin of dolomite porosity and demonstrates the porosity evolution and reservoir characteristics of different dolomite types.

  13. Molecular Epidemiology of Blastocystis sp. in Various Animal Groups from Two French Zoos and Evaluation of Potential Zoonotic Risk.

    PubMed

    Cian, Amandine; El Safadi, Dima; Osman, Marwan; Moriniere, Romain; Gantois, Nausicaa; Benamrouz-Vanneste, Sadia; Delgado-Viscogliosi, Pilar; Guyot, Karine; Li, Luen-Luen; Monchy, Sébastien; Noël, Christophe; Poirier, Philippe; Nourrisson, Céline; Wawrzyniak, Ivan; Delbac, Frédéric; Bosc, Stéphanie; Chabé, Magali; Petit, Thierry; Certad, Gabriela; Viscogliosi, Eric

    2017-01-01

    Blastocystis sp. is a common intestinal parasite infecting humans and a wide range of animals worldwide. It exhibits an extensive genetic diversity and 17 subtypes (STs) have thus far been identified in mammalian and avian hosts. Since several STs are common to humans and animals, it was proposed that a proportion of human infections may result from zoonotic transmission. However, the contribution of each animal source to human infection remains to be clarified. Therefore, the aim of this study was to expand our knowledge of the epidemiology and host specificity of this parasite by performing the largest epidemiological survey ever conducted in animal groups in terms of numbers of species screened. A total of 307 stool samples from 161 mammalian and non-mammalian species in two French zoos were screened by real-time PCR for the presence of Blastocystis sp. Overall, 32.2% of the animal samples and 37.9% of the species tested were shown to be infected with the parasite. A total of 111 animal Blastocystis sp. isolates were subtyped, and 11 of the 17 mammalian and avian STs as well as additional STs previously identified in reptiles and insects were found with a varying prevalence according to animal groups. These data were combined with those obtained from previous surveys to evaluate the potential risk of zoonotic transmission of Blastocystis sp. through the comparison of ST distribution between human and animal hosts. This suggests that non-human primates, artiodactyls and birds may serve as reservoirs for human infection, especially in animal handlers. In contrast, other mammals such as carnivores, and non-mammalian groups including reptiles and insects, do not seem to represent significant sources of Blastocystis sp. infection in humans. In further studies, more intensive sampling and screening of potential new animal hosts will reinforce these statements and expand our understanding of the circulation of Blastocystis sp. in animal and human populations.

  14. Molecular Epidemiology of Blastocystis sp. in Various Animal Groups from Two French Zoos and Evaluation of Potential Zoonotic Risk

    PubMed Central

    Moriniere, Romain; Gantois, Nausicaa; Benamrouz-Vanneste, Sadia; Delgado-Viscogliosi, Pilar; Guyot, Karine; Li, Luen-Luen; Monchy, Sébastien; Noël, Christophe; Poirier, Philippe; Nourrisson, Céline; Wawrzyniak, Ivan; Delbac, Frédéric; Bosc, Stéphanie; Chabé, Magali; Petit, Thierry; Certad, Gabriela; Viscogliosi, Eric

    2017-01-01

    Blastocystis sp. is a common intestinal parasite infecting humans and a wide range of animals worldwide. It exhibits an extensive genetic diversity and 17 subtypes (STs) have thus far been identified in mammalian and avian hosts. Since several STs are common to humans and animals, it was proposed that a proportion of human infections may result from zoonotic transmission. However, the contribution of each animal source to human infection remains to be clarified. Therefore, the aim of this study was to expand our knowledge of the epidemiology and host specificity of this parasite by performing the largest epidemiological survey ever conducted in animal groups in terms of numbers of species screened. A total of 307 stool samples from 161 mammalian and non-mammalian species in two French zoos were screened by real-time PCR for the presence of Blastocystis sp. Overall, 32.2% of the animal samples and 37.9% of the species tested were shown to be infected with the parasite. A total of 111 animal Blastocystis sp. isolates were subtyped, and 11 of the 17 mammalian and avian STs as well as additional STs previously identified in reptiles and insects were found with a varying prevalence according to animal groups. These data were combined with those obtained from previous surveys to evaluate the potential risk of zoonotic transmission of Blastocystis sp. through the comparison of ST distribution between human and animal hosts. This suggests that non-human primates, artiodactyls and birds may serve as reservoirs for human infection, especially in animal handlers. In contrast, other mammals such as carnivores, and non-mammalian groups including reptiles and insects, do not seem to represent significant sources of Blastocystis sp. infection in humans. In further studies, more intensive sampling and screening of potential new animal hosts will reinforce these statements and expand our understanding of the circulation of Blastocystis sp. in animal and human populations. PMID

  15. Non-human vertebrate hosts of Schistosoma haematobium and Schistosoma mansoni

    PubMed Central

    Martins, A. Vianna

    1958-01-01

    The author reviews the results of experimental infections of various species of mammals, other than man, with S. haematobium and S. mansoni, and discusses investigations in Africa and Brazil into the possibility of the natural infection of non-human vertebrates with these two parasites. Only a few species, besides monkeys, could be easily infected with S. haematobium in the laboratory, while—outside man—natural infection with this parasite appears to be practically non-existent. On the other hand, many animals are good experimental hosts for S. mansoni, and at least 21 species of mammals have been found infected with this parasite in Africa and America. It is thus possible to state, provisionally, that man is the only reservoir of S. haematobium, but the question still remains open where S. mansoni is concerned. Further research is suggested in order to assess the importance of non-human reservoirs in the epidemiology of bilharziasis. PMID:13573118

  16. [Ixodes ricinus, transmitted diseases and reservoirs].

    PubMed

    Rizzoli, A; Rosà, R; Mantelli, B; Pecchioli, E; Hauffe, H; Tagliapietra, V; Beninati, T; Neteler, M; Genchi, C

    2004-06-01

    The tick Ixodes ricinus has been recorded in most Italian regions especially in thermo-mesophilous woods and shrubby habitats where the relative humidity allow the tick to complete its 3 year developmental cycle, as predicted for the European climatic ranges. This tick acts both as vector and reservoir for a series of wildlife zoonotic pathogens, especially the agents of Lyme diseases, Tick borne encephalitis and Human Granulocytic Ehrlichiosis, which are emerging in most of Europe. To assess the spatial distribution of these pathogens and the infection risk for humans and animals within the territory of the Province of Trento, we carried out a long term study using a combination of eco-epidemiological surveys and mathematical modelling. An extensive tick collection with a GIS based habitat suitability analysis allowed us to identify the areas where tick occurs at various density. To identify the areas with higher infection risk, we estimated the values of R0 for Borrelia burgdorferi s.l., TBE virus and Anaplasma phagocytophila under different ecological conditions. We assessed the infection prevalence in the vector and in the wildlife reservoir species that play a central role in the persistence of these infections, ie the small mammals A. flavicollis and C. glareolus. We also considered the double effect of roe deer (Capreolus capreolus) which act as reservoir for A. phagocytophila but is an incompetent host for B. burgdorferi and TBE virus, thus reducing the infection prevalence in ticks of these last two pathogens. Infection prevalence with B. burgdorferi and A. phagocytophila in the vector was assessed by PCR screening 1212 I. ricinus nymphs collected by dragging in six main study areas during 2002. The mean infection prevalence recorded was 1.32% for B. burgdorferi s.l. and 9.84% for A. phagocytophila. Infection prevalence in nymphs with TBE virus, as assessed in a previous study was 0.03%. Infection prevalence in rodents was assessed by screening (with ELISA

  17. Zoonoses of occupational health importance in contemporary laboratory animal research.

    PubMed

    Hankenson, F Claire; Johnston, Nancy A; Weigler, Benjamin J; Di Giacomo, Ronald F

    2003-12-01

    In contemporary laboratory animal facilities, workplace exposure to zoonotic pathogens, agents transmitted to humans from vertebrate animals or their tissues, is an occupational hazard. The primary (e.g., macaques, pigs, dogs, rabbits, mice, and rats) and secondary species (e.g., sheep, goats, cats, ferrets, and pigeons) of animals commonly used in biomedical research, as classified by the American College of Laboratory Animal Medicine, are established or potential hosts for a large number of zoonotic agents. Diseases included in this review are principally those wherein a risk to biomedical facility personnel has been documented by published reports of human cases in laboratory animal research settings, or under reasonably similar circumstances. Diseases are listed alphabetically, and each section includes information about clinical disease, transmission, occurrence, and prevention in animal reservoir species and humans. Our goal is to provide a resource for veterinarians, health-care professionals, technical staff, and administrators that will assist in the design and on-going evaluation of institutional occupational health and safety programs.

  18. Animal Model of Dermatophytosis

    PubMed Central

    Shimamura, Tsuyoshi; Kubota, Nobuo; Shibuya, Kazutoshi

    2012-01-01

    Dermatophytosis is superficial fungal infection caused by dermatophytes that invade the keratinized tissue of humans and animals. Lesions from dermatophytosis exhibit an inflammatory reaction induced to eliminate the invading fungi by using the host's normal immune function. Many scientists have attempted to establish an experimental animal model to elucidate the pathogenesis of human dermatophytosis and evaluate drug efficacy. However, current animal models have several issues. In the present paper, we surveyed reports about the methodology of the dermatophytosis animal model for tinea corporis, tinea pedis, and tinea unguium and discussed future prospects. PMID:22619489

  19. When Viruses Don’t Go Viral: The Importance of Host Phylogeographic Structure in the Spatial Spread of Arenaviruses

    PubMed Central

    Baird, Stuart J. E.; Goüy de Bellocq, Joëlle

    2017-01-01

    Many emerging infections are RNA virus spillovers from animal reservoirs. Reservoir identification is necessary for predicting the geographic extent of infection risk, but rarely are taxonomic levels below the animal species considered as reservoir, and only key circumstances in nature and methodology allow intrinsic virus-host associations to be distinguished from simple geographic (co-)isolation. We sampled and genetically characterized in detail a contact zone of two subtaxa of the rodent Mastomys natalensis in Tanzania. We find two distinct arenaviruses, Gairo and Morogoro virus, each spatially confined to a single M. natalensis subtaxon, only co-occurring at the contact zone’s centre. Inter-subtaxon hybridization at this centre and a continuum of quality habitat for M. natalensis show that both viruses have the ecological opportunity to spread into the other substaxon’s range, but do not, strongly suggesting host-intrinsic barriers. Such barriers could explain why human cases of another M. natalensis-borne arenavirus, Lassa virus, are limited to West Africa. PMID:28076397

  20. Prospects of host-associated microorganisms in fish and penaeids as probiotics with immunomodulatory functions.

    PubMed

    Lazado, Carlo C; Caipang, Christopher Marlowe A; Estante, Erish G

    2015-07-01

    Aquatic animals harbor a great number of microorganisms with interesting biological and biochemical diversity. Besides serving as the natural defense system of the host, the utilization potential of this microbial association has been identified particularly as reservoirs of candidate probiotics. Host-derived probiotics have gained popularity in recent years as they offer an alternative source of beneficial microbes to the industry that is customarily dependent on the use of terrestrial microorganisms. At present, there is an overwhelming number of candidate probiotics in aquaculture but their large-scale application is restricted by bio-technological concerns and fragmentary documented probiotic actions. This paper presents the current understanding on the use of probiotics as a sustainable alternative that promotes health and welfare in fish and penaeids. In particular, this paper discusses the relevance of host microbiota and its potential as a source of candidate probiotics. It also revisits the interaction between probiotics and host immunity to provide the foundation of the immunomodulatory functions of host-derived probiotics. Several studies demonstrating the immunomodulatory capabilities of host-derived candidate probiotics are given to establish the current knowledge and provide avenues for future research and development in this thematic area of probiotics research in aquaculture.

  1. 95. BOUQUET RESERVOIR LOOKING UP VALLEY TO RESERVOIR LOOKING EAST ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    95. BOUQUET RESERVOIR LOOKING UP VALLEY TO RESERVOIR LOOKING EAST - Los Angeles Aqueduct, From Lee Vining Intake (Mammoth Lakes) to Van Norman Reservoir Complex (San Fernando Valley), Los Angeles, Los Angeles County, CA

  2. Tick-borne infections in human and animal population worldwide.

    PubMed

    Brites-Neto, José; Duarte, Keila Maria Roncato; Martins, Thiago Fernandes

    2015-03-01

    The abundance and activity of ectoparasites and its hosts are affected by various abiotic factors, such as climate and other organisms (predators, pathogens and competitors) presenting thus multiples forms of association (obligate to facultative, permanent to intermittent and superficial to subcutaneous) developed during long co-evolving processes. Ticks are ectoparasites widespread globally and its eco epidemiology are closely related to the environmental conditions. They are obligatory hematophagous ectoparasites and responsible as vectors or reservoirs at the transmission of pathogenic fungi, protozoa, viruses, rickettsia and others bacteria during their feeding process on the hosts. Ticks constitute the second vector group that transmit the major number of pathogens to humans and play a role primary for animals in the process of diseases transmission. Many studies on bioecology of ticks, considering the information related to their population dynamics, to the host and the environment, comes possible the application and efficiency of tick control measures in the prevention programs of vector-borne diseases. In this review were considered some taxonomic, morphological, epidemiological and clinical fundamental aspects related to the tick-borne infections that affect human and animal populations.

  3. Tick-borne infections in human and animal population worldwide

    PubMed Central

    Brites-Neto, José; Duarte, Keila Maria Roncato; Martins, Thiago Fernandes

    2015-01-01

    The abundance and activity of ectoparasites and its hosts are affected by various abiotic factors, such as climate and other organisms (predators, pathogens and competitors) presenting thus multiples forms of association (obligate to facultative, permanent to intermittent and superficial to subcutaneous) developed during long co-evolving processes. Ticks are ectoparasites widespread globally and its eco epidemiology are closely related to the environmental conditions. They are obligatory hematophagous ectoparasites and responsible as vectors or reservoirs at the transmission of pathogenic fungi, protozoa, viruses, rickettsia and others bacteria during their feeding process on the hosts. Ticks constitute the second vector group that transmit the major number of pathogens to humans and play a role primary for animals in the process of diseases transmission. Many studies on bioecology of ticks, considering the information related to their population dynamics, to the host and the environment, comes possible the application and efficiency of tick control measures in the prevention programs of vector-borne diseases. In this review were considered some taxonomic, morphological, epidemiological and clinical fundamental aspects related to the tick-borne infections that affect human and animal populations. PMID:27047089

  4. Reservoir Inflation Schedule

    SciTech Connect

    Ponden, Raymond F.

    1991-11-22

    Inflation of the reservoir is to begin on Friday afternoon, November 22 and continue through mid day on Monday, November 25. Inflation of the reservoir shall be accomplished by using only injection pump, HP-2. NOTE: Under no circumstances should injection pump, HP-1 be operated.

  5. Undiscovered Bat Hosts of Filoviruses

    PubMed Central

    Schmidt, John Paul; Alexander, Laura W.; Bowden, Sarah E.; Hayman, David T. S.; Drake, John M.

    2016-01-01

    Ebola and other filoviruses pose significant public health and conservation threats by causing high mortality in primates, including humans. Preventing future outbreaks of ebolavirus depends on identifying wildlife reservoirs, but extraordinarily high biodiversity of potential hosts in temporally dynamic environments of equatorial Africa contributes to sporadic, unpredictable outbreaks that have hampered efforts to identify wild reservoirs for nearly 40 years. Using a machine learning algorithm, generalized boosted regression, we characterize potential filovirus-positive bat species with estimated 87% accuracy. Our model produces two specific outputs with immediate utility for guiding filovirus surveillance in the wild. First, we report a profile of intrinsic traits that discriminates hosts from non-hosts, providing a biological caricature of a filovirus-positive bat species. This profile emphasizes traits describing adult and neonate body sizes and rates of reproductive fitness, as well as species’ geographic range overlap with regions of high mammalian diversity. Second, we identify several bat species ranked most likely to be filovirus-positive on the basis of intrinsic trait similarity with known filovirus-positive bats. New bat species predicted to be positive for filoviruses are widely distributed outside of equatorial Africa, with a majority of species overlapping in Southeast Asia. Taken together, these results spotlight several potential host species and geographical regions as high-probability targets for future filovirus surveillance. PMID:27414412

  6. Geothermal reservoir engineering research

    NASA Technical Reports Server (NTRS)

    Ramey, H. J., Jr.; Kruger, P.; Brigham, W. E.; London, A. L.

    1974-01-01

    The Stanford University research program on the study of stimulation and reservoir engineering of geothermal resources commenced as an interdisciplinary program in September, 1972. The broad objectives of this program have been: (1) the development of experimental and computational data to evaluate the optimum performance of fracture-stimulated geothermal reservoirs; (2) the development of a geothermal reservoir model to evaluate important thermophysical, hydrodynamic, and chemical parameters based on fluid-energy-volume balances as part of standard reservoir engineering practice; and (3) the construction of a laboratory model of an explosion-produced chimney to obtain experimental data on the processes of in-place boiling, moving flash fronts, and two-phase flow in porous and fractured hydrothermal reservoirs.

  7. Architecture of collapsed-paleocave reservoirs

    SciTech Connect

    Loucks, R.G. ); Mescher, P. )

    1996-01-01

    It is important to investigate the architecture of collapsed-paleocave reservoirs at interwell scales in outcrops because reservoir heterogeneities cannot be adequately characterized by cores and log correlation sections. A 3000-foot long quarry wall of Ellenburger strata in central Texas displays the lithologic and pore network heterogeneities at typical well spacings (1300 to 2600 feet). The quarry wall exposes the transition from stratified host rock into a complex collapsed-paleocave system showing several developmental episodes. This paleocave system has over 2600 feet of laterally continuous chaotic breccias. The dimensions of these breccias are similar as to what is imaged by 3-D seismic over paleocave reservoirs. Collapsed-paleocave reservoirs are not single collapsed passages of tens of feet across, but are homogenized collapsed-cave systems hundreds to several thousand feet across. This concept of scale is very important because collapsed-paleocave systems offer larger exploration targets than individual cave passages. Collapsed-paleocave systems are complex because they are the homogenization of chaotic breccias and cave-sediment fill from passages, chambers, and shafts and of crackle breccias from roof- and wall-rock and pillars. Pore networks are associated with chaotic breakdown breccias, cave roof- and wall-crackle breccias, and/or clastic sediment fill. Strong heterogeneity within a collapsed paleocave system should be expected. Lateral and vertical changes in collapsed-paleocave-related facies have the strongest effect on reservoir heterogeneity and quality. Within individual facies there can be distinct reservoir quality variation, such as between the cave-sediment fill and associated blocks. Tectonic fractures, however, can interconnect the highly variable pore networks within a collapsed-paleocave reservoir.

  8. Architecture of collapsed-paleocave reservoirs

    SciTech Connect

    Loucks, R.G.; Mescher, P.

    1996-12-31

    It is important to investigate the architecture of collapsed-paleocave reservoirs at interwell scales in outcrops because reservoir heterogeneities cannot be adequately characterized by cores and log correlation sections. A 3000-foot long quarry wall of Ellenburger strata in central Texas displays the lithologic and pore network heterogeneities at typical well spacings (1300 to 2600 feet). The quarry wall exposes the transition from stratified host rock into a complex collapsed-paleocave system showing several developmental episodes. This paleocave system has over 2600 feet of laterally continuous chaotic breccias. The dimensions of these breccias are similar as to what is imaged by 3-D seismic over paleocave reservoirs. Collapsed-paleocave reservoirs are not single collapsed passages of tens of feet across, but are homogenized collapsed-cave systems hundreds to several thousand feet across. This concept of scale is very important because collapsed-paleocave systems offer larger exploration targets than individual cave passages. Collapsed-paleocave systems are complex because they are the homogenization of chaotic breccias and cave-sediment fill from passages, chambers, and shafts and of crackle breccias from roof- and wall-rock and pillars. Pore networks are associated with chaotic breakdown breccias, cave roof- and wall-crackle breccias, and/or clastic sediment fill. Strong heterogeneity within a collapsed paleocave system should be expected. Lateral and vertical changes in collapsed-paleocave-related facies have the strongest effect on reservoir heterogeneity and quality. Within individual facies there can be distinct reservoir quality variation, such as between the cave-sediment fill and associated blocks. Tectonic fractures, however, can interconnect the highly variable pore networks within a collapsed-paleocave reservoir.

  9. A Massive Molecular Gas Reservoir in the Z = 2.221 Type-2 Quasar Host Galaxy SMM J0939+8315 Lensed by the Radio Galaxy 3C220.3

    NASA Astrophysics Data System (ADS)

    Leung, T. K. Daisy; Riechers, Dominik A.

    2016-02-01

    We report the detection of CO(J = 3 \\to 2) line emission in the strongly lensed submillimeter galaxy (SMG) SMM J0939+8315 at z = 2.221, using the Combined Array for Research in Millimeter-wave Astronomy. SMM J0939+8315 hosts a type-2 quasar, and is gravitationally lensed by the radio galaxy 3C220.3 and its companion galaxy at z = 0.685. The 104 GHz continuum emission underlying the CO line is detected toward 3C220.3 with an integrated flux density of Scont = 7.4 ± 1.4 mJy. Using the CO(J = 3 \\to 2) line intensity of ICO(3-2) = (12.6 ± 2.0) Jy km s-1, we derive a lensing- and excitation-corrected CO line luminosity of {L}{{CO(1-0)}}\\prime = (3.4 ± 0.7) × 1010 (10.1/μL) K km s-1 pc2 for the SMG, where μL is the lensing magnification factor inferred from our lens modeling. This translates to a molecular gas mass of Mgas = (2.7 ± 0.6) × 1010 (10.1/μL) M⊙. Fitting spectral energy distribution models to the (sub)-millimeter data of this SMG yields a dust temperature of T = 63.1{}-1.3+1.1 K, a dust mass of Mdust = (5.2 ± 2.1) × 108 (10.1/μL) M⊙, and a total infrared luminosity of LIR = (9.1 ± 1.2) ×1012 (10.1/μL) L⊙. We find that the properties of the interstellar medium of SMM J0939+8315 overlap with both SMGs and type-2 quasars. Hence, SMM J0939+8315 may be transitioning from a starbursting phase to an unobscured quasar phase as described by the “evolutionary link” model, according to which this system may represent an intermediate stage in the evolution of present-day galaxies at an earlier epoch.

  10. Simultaneous identification of host, ectoparasite and pathogen DNA via in-solution capture.

    PubMed

    Campana, Michael G; Hawkins, Melissa T R; Henson, Lauren H; Stewardson, Kristin; Young, Hillary S; Card, Leah R; Lock, Justin; Agwanda, Bernard; Brinkerhoff, Jory; Gaff, Holly D; Helgen, Kristofer M; Maldonado, Jesús E; McShea, William J; Fleischer, Robert C

    2016-09-01

    Ectoparasites frequently vector pathogens from often unknown pathogen reservoirs to both human and animal populations. Simultaneous identification of the ectoparasite species, the wildlife host that provided their most recent blood meal(s), and their pathogen load would greatly facilitate the understanding of the complex transmission dynamics of vector-borne diseases. Currently, these identifications are principally performed using multiple polymerase chain reaction (PCR) assays. We developed an assay (EctoBaits) based on in-solution capture paired with high-throughput sequencing to simultaneously identify ectoparasites, host blood meals and pathogens. We validated our in-solution capture results using double-blind PCR assays, morphology and collection data. The EctoBaits assay effectively and efficiently identifies ectoparasites, blood meals, and pathogens in a single capture experiment, allowing for high-resolution taxonomic identification while preserving the DNA sample for future analyses.

  11. Wild and synanthropic reservoirs of Leishmania species in the Americas

    PubMed Central

    Roque, André Luiz R.; Jansen, Ana Maria

    2014-01-01

    The definition of a reservoir has changed significantly in the last century, making it necessary to study zoonosis from a broader perspective. One important example is that of Leishmania, zoonotic multi-host parasites maintained by several mammal species in nature. The magnitude of the health problem represented by leishmaniasis combined with the complexity of its epidemiology make it necessary to clarify all of the links in transmission net, including non-human mammalian hosts, to develop effective control strategies. Although some studies have described dozens of species infected with these parasites, only a minority have related their findings to the ecological scenario to indicate a possible role of that host in parasite maintenance and transmission. Currently, it is accepted that a reservoir may be one or a complex of species responsible for maintaining the parasite in nature. A reservoir system should be considered unique on a given spatiotemporal scale. In fact, the transmission of Leishmania species in the wild still represents an complex enzootic “puzzle”, as several links have not been identified. This review presents the mammalian species known to be infected with Leishmania spp. in the Americas, highlighting those that are able to maintain and act as a source of the parasite in nature (and are thus considered potential reservoirs). These host/reservoirs are presented separately in each of seven mammal orders – Marsupialia, Cingulata, Pilosa, Rodentia, Primata, Carnivora, and Chiroptera – responsible for maintaining Leishmania species in the wild. PMID:25426421

  12. Biology of Cryptosporidium from marsupial hosts.

    PubMed

    Power, Michelle L

    2010-01-01

    The majority of biological data on Cryptosporidium has been collected from humans and domestic animal hosts which creates a bias in knowledge on the biodiversity and evolution of this parasite genus. Further to understanding Cryptosporidium biology are studies encompassing broad hosts that represent diverse taxa sampled across wide geographic ranges. Marsupials represent a group of wildlife hosts from which limited information on Cryptosporidium is available. As marsupial hosts are an ancient mammalian lineage they represent an important group for studying parasite evolution. This review summarises information of the biology, epidemiology and evolution of Cryptosporidium in marsupial hosts, and discusses the importance of further understanding interactions in this parasite-host system.

  13. New hosts for equine herpesvirus 9.

    PubMed

    Schrenzel, Mark D; Tucker, Tammy A; Donovan, Taryn A; Busch, Martin D M; Wise, Annabel G; Maes, Roger K; Kiupel, Matti

    2008-10-01

    Equine herpesvirus 9 was detected in a polar bear with progressive encephalitis; the source was traced to 2 members of a potential equid reservoir species, Grevy's zebras. The virus was also found in an aborted Persian onager. Thus, the natural host range is extended to 6 species in 3 mammalian orders.

  14. New Hosts for Equine Herpesvirus 9

    PubMed Central

    Tucker, Tammy A.; Donovan, Taryn A.; Busch, Martin D.M.; Wise, Annabel G.; Maes, Roger K.; Kiupel, Matti

    2008-01-01

    Equine herpesvirus 9 was detected in a polar bear with progressive encephalitis; the source was traced to 2 members of a potential equid reservoir species, Grevy’s zebras. The virus was also found in an aborted Persian onager. Thus, the natural host range is extended to 6 species in 3 mammalian orders. PMID:18826828

  15. Reservoir Temperature Estimator

    SciTech Connect

    Palmer, Carl D.

    2014-12-08

    The Reservoir Temperature Estimator (RTEst) is a program that can be used to estimate deep geothermal reservoir temperature and chemical parameters such as CO2 fugacity based on the water chemistry of shallower, cooler reservoir fluids. This code uses the plugin features provided in The Geochemist’s Workbench (Bethke and Yeakel, 2011) and interfaces with the model-independent parameter estimation code Pest (Doherty, 2005) to provide for optimization of the estimated parameters based on the minimization of the weighted sum of squares of a set of saturation indexes from a user-provided mineral assemblage.

  16. Ecologic studies of rodent reservoirs: their relevance for human health.

    PubMed Central

    Mills, J. N.; Childs, J. E.

    1998-01-01

    Within the past few years, the number of "new" human diseases associated with small-mammal reservoirs has increased dramatically, stimulating renewed interest in reservoir ecology research. A consistent, integrative approach to such research allows direct comparisons between studies, contributes to the efficient use of resources and data, and increases investigator safety. We outline steps directed toward understanding vertebrate host ecology as it relates to human disease and illustrate the relevance of each step by using examples from studies of hosts associated with rodent-borne hemorrhagic fever viruses. PMID:9866729

  17. Patterns of gregarine parasitism in dragonflies: host, habitat, and seasonality.

    PubMed

    Locklin, Jason L; Vodopich, Darrell S

    2010-06-01

    Gregarines are ubiquitous protozoan parasites that infect arthropods worldwide. More than 1,600 gregarine species have been described, but only a small percentage of invertebrates have been surveyed for these apicomplexan parasites. Adult dragonfly populations were surveyed for gregarines at two reservoirs in Texas, USA for 2 years. Gregarine prevalence and intensity were compared intraspecifically between host genders and reservoirs, among wing loads, and through time. Of the 29 dragonfly species collected, 41% hosted gregarines. Nine of these dragonfly species were previously undocumented as hosts. Among the commonly collected hosts, prevalence ranged from 18 to 52%. Parasites were aggregated among hosts and had a median intensity of five parasites per host. Gregarines were found only in hosts exceeding a minimum wing load, indicating that gregarines are likely not transferred from the naiad to adult during emergence. Prevalence and intensity increased during both years, suggesting that gregarine oocyst viability parallels increasing host population densities and may be short-lived. Prevalence and intensity also differed between dragonfly populations at two reservoirs. Regression analyses revealed that host species, host gender, month, and year were significant explanatory variables related to gregarine prevalence and intensity. Abundant information on odonate distributions, diversity, and mating activities makes dragonfly-gregarine systems excellent avenues for ecological, evolutionary, and parasitological research. Our results emphasize the importance of considering season, hosts, and habitat when studying gregarine-dragonfly ecology.

  18. Immunological Mechanisms Mediating Hantavirus Persistence in Rodent Reservoirs

    PubMed Central

    Easterbrook, Judith D.; Klein, Sabra L.

    2008-01-01

    Hantaviruses, similar to several emerging zoonotic viruses, persistently infect their natural reservoir hosts, without causing overt signs of disease. Spillover to incidental human hosts results in morbidity and mortality mediated by excessive proinflammatory and cellular immune responses. The mechanisms mediating the persistence of hantaviruses and the absence of clinical symptoms in rodent reservoirs are only starting to be uncovered. Recent studies indicate that during hantavirus infection, proinflammatory and antiviral responses are reduced and regulatory responses are elevated at sites of increased virus replication in rodents. The recent discovery of structural and non-structural proteins that suppress type I interferon responses in humans suggests that immune responses in rodent hosts could be mediated directly by the virus. Alternatively, several host factors, including sex steroids, glucocorticoids, and genetic factors, are reported to alter host susceptibility and may contribute to persistence of hantaviruses in rodents. Humans and reservoir hosts differ in infection outcomes and in immune responses to hantavirus infection; thus, understanding the mechanisms mediating viral persistence and the absence of disease in rodents may provide insight into the prevention and treatment of disease in humans. Consideration of the coevolutionary mechanisms mediating hantaviral persistence and rodent host survival is providing insight into the mechanisms by which zoonotic viruses have remained in the environment for millions of years and continue to be transmitted to humans. PMID:19043585

  19. Amazing Animals

    ERIC Educational Resources Information Center

    Al-Kuwari, Najat Saad

    2007-01-01

    "Animals" is a three-part lesson plan for young learners with a zoo animal theme. The first lesson is full of activities to describe animals, with Simon Says, guessing games, and learning stations. The second lesson is about desert animals, but other types of animals could be chosen depending on student interest. This lesson teaches…

  20. Reservoir characterization of Pennsylvanian sandstone reservoirs. Final report

    SciTech Connect

    Kelkar, M.

    1995-02-01

    This final report summarizes the progress during the three years of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description; (ii) scale-up procedures; (iii) outcrop investigation. The first section describes the methods by which a reservoir can be described in three dimensions. The next step in reservoir description is to scale up reservoir properties for flow simulation. The second section addresses the issue of scale-up of reservoir properties once the spatial descriptions of properties are created. The last section describes the investigation of an outcrop.

  1. Geysers reservoir studies

    SciTech Connect

    Bodvarsson, G.S.; Lippmann, M.J.; Pruess, K. )

    1993-01-01

    Lawrence Berkeley Laboratory is conducting several research projects related to issues of interest to The Geysers operators, including those that deal with understanding the nature of vapor-dominated systems, measuring or inferring reservoir processes and parameters, and studying the effects of liquid injection. All of these topics are directly or indirectly relevant to the development of reservoir strategies aimed at stabilizing or increasing production rates of non-corrosive steam, low in non-condensable gases. Three reservoir engineering studies are described in some detail, that is: (a) Modeling studies of heat transfer and phase distribution in two-phase geothermal reservoirs; (b) Numerical modeling studies of Geysers injection experiments; and (c) Development of a dual-porosity model to calculate mass flow between rock matrix blocks and neighboring fractures.

  2. Potential Mammalian Filovirus Reservoirs

    PubMed Central

    Carroll, Darin S.; Mills, James N.; Johnson, Karl M.

    2004-01-01

    Ebola and Marburg viruses are maintained in unknown reservoir species; spillover into human populations results in occasional human cases or epidemics. We attempted to narrow the list of possibilities regarding the identity of those reservoir species. We made a series of explicit assumptions about the reservoir: it is a mammal; it supports persistent, largely asymptomatic filovirus infections; its range subsumes that of its associated filovirus; it has coevolved with the virus; it is of small body size; and it is not a species that is commensal with humans. Under these assumptions, we developed priority lists of mammal clades that coincide distributionally with filovirus outbreak distributions and compared these lists with those mammal taxa that have been tested for filovirus infection in previous epidemiologic studies. Studying the remainder of these taxa may be a fruitful avenue for pursuing the identity of natural reservoirs of filoviruses. PMID:15663841

  3. Salmonellae interactions with host processes.

    PubMed

    LaRock, Doris L; Chaudhary, Anu; Miller, Samuel I

    2015-04-01

    Salmonellae invasion and intracellular replication within host cells result in a range of diseases, including gastroenteritis, bacteraemia, enteric fever and focal infections. In recent years, considerable progress has been made in our understanding of the molecular mechanisms that salmonellae use to alter host cell physiology; through the delivery of effector proteins with specific activities and through the modulation of defence and stress response pathways. In this Review, we summarize our current knowledge of the complex interplay between bacterial and host factors that leads to inflammation, disease and, in most cases, control of the infection by its animal hosts, with a particular focus on Salmonella enterica subsp. enterica serovar Typhimurium. We also highlight gaps in our knowledge of the contributions of salmonellae and the host to disease pathogenesis, and we suggest future avenues for further study.

  4. Geothermal reservoir simulation

    NASA Technical Reports Server (NTRS)

    Mercer, J. W., Jr.; Faust, C.; Pinder, G. F.

    1974-01-01

    The prediction of long-term geothermal reservoir performance and the environmental impact of exploiting this resource are two important problems associated with the utilization of geothermal energy for power production. Our research effort addresses these problems through numerical simulation. Computer codes based on the solution of partial-differential equations using finite-element techniques are being prepared to simulate multiphase energy transport, energy transport in fractured porous reservoirs, well bore phenomena, and subsidence.

  5. Session: Reservoir Technology

    SciTech Connect

    Renner, Joel L.; Bodvarsson, Gudmundur S.; Wannamaker, Philip E.; Horne, Roland N.; Shook, G. Michael

    1992-01-01

    This session at the Geothermal Energy Program Review X: Geothermal Energy and the Utility Market consisted of five papers: ''Reservoir Technology'' by Joel L. Renner; ''LBL Research on the Geysers: Conceptual Models, Simulation and Monitoring Studies'' by Gudmundur S. Bodvarsson; ''Geothermal Geophysical Research in Electrical Methods at UURI'' by Philip E. Wannamaker; ''Optimizing Reinjection Strategy at Palinpinon, Philippines Based on Chloride Data'' by Roland N. Horne; ''TETRAD Reservoir Simulation'' by G. Michael Shook

  6. Animal Bites

    MedlinePlus

    ... Ear Nose & Throat Emotional Problems Eyes Fever From Insects or Animals Genitals and Urinary Tract Glands & Growth ... Preventable Diseases Healthy Children > Health Issues > Conditions > From Insects or Animals > Animal Bites Health Issues Listen Español ...

  7. Andrew integrated reservoir description

    SciTech Connect

    Todd, S.P.

    1996-12-31

    The Andrew field is an oil and gas accumulation in Palaeocene deep marine sands in the Central North Sea. It is currently being developed with mainly horizontal oil producers. Because of the field`s relatively small reserves (mean 118 mmbbls), the performance of each of the 10 or so horizontal wells is highly important. Reservoir description work at sanction time concentrated on supporting the case that the field could be developed commercially with the minimum number of wells. The present Integrated Reservoir Description (IRD) is focussed on delivering the next level of detail that will impact the understanding of the local reservoir architecture and dynamic performance of each well. Highlights of Andrew IRD Include: (1) Use of a Reservoir Uncertainty Statement (RUS) developed at sanction time to focus the descriptive effort of both asset, support and contract petrotechnical staff, (2) High resolution biostratigraphic correlation to support confident zonation of the reservoir, (3) Detailed sedimentological analysis of the core including the use of dipmeter to interpret channel/sheet architecture to provide new insights into reservoir heterogeneity; (4) Integrated petrographical and petrophysical investigation of the controls on Sw-Height and relative permeability of water; (5) Fluids description using oil geochemistry and Residual Salt Analysis Sr isotope studies. Andrew IRD has highlighted several important risks to well performance, including the influence of more heterolithic intervals on gas breakthrough and the controls on water coning exerted by suppressed water relative permeability in the transition zone.

  8. Andrew integrated reservoir description

    SciTech Connect

    Todd, S.P.

    1996-01-01

    The Andrew field is an oil and gas accumulation in Palaeocene deep marine sands in the Central North Sea. It is currently being developed with mainly horizontal oil producers. Because of the field's relatively small reserves (mean 118 mmbbls), the performance of each of the 10 or so horizontal wells is highly important. Reservoir description work at sanction time concentrated on supporting the case that the field could be developed commercially with the minimum number of wells. The present Integrated Reservoir Description (IRD) is focussed on delivering the next level of detail that will impact the understanding of the local reservoir architecture and dynamic performance of each well. Highlights of Andrew IRD Include: (1) Use of a Reservoir Uncertainty Statement (RUS) developed at sanction time to focus the descriptive effort of both asset, support and contract petrotechnical staff, (2) High resolution biostratigraphic correlation to support confident zonation of the reservoir, (3) Detailed sedimentological analysis of the core including the use of dipmeter to interpret channel/sheet architecture to provide new insights into reservoir heterogeneity; (4) Integrated petrographical and petrophysical investigation of the controls on Sw-Height and relative permeability of water; (5) Fluids description using oil geochemistry and Residual Salt Analysis Sr isotope studies. Andrew IRD has highlighted several important risks to well performance, including the influence of more heterolithic intervals on gas breakthrough and the controls on water coning exerted by suppressed water relative permeability in the transition zone.

  9. Workshop on molecular animation.

    PubMed

    Bromberg, Sarina; Chiu, Wah; Ferrin, Thomas E

    2010-10-13

    From February 25 to 26, 2010, in San Francisco, the Resource for Biocomputing, Visualization, and Informatics (RBVI) and the National Center for Macromolecular Imaging (NCMI) hosted a molecular animation workshop for 21 structural biologists, molecular animators, and creators of molecular visualization software. Molecular animation aims to visualize scientific understanding of biomolecular processes and structures. The primary goal of the workshop was to identify the necessary tools for producing high-quality molecular animations, understanding complex molecular and cellular structures, creating publication supplementary materials and conference presentations, and teaching science to students and the public. Another use of molecular animation emerged in the workshop: helping to focus scientific inquiry about the motions of molecules and enhancing informal communication within and between laboratories.

  10. Workshop on Molecular Animation

    PubMed Central

    Bromberg, Sarina; Chiu, Wah; Ferrin, Thomas E.

    2011-01-01

    Summary February 25–26, 2010, in San Francisco, the Resource for Biocomputing, Visualization and Informatics (RBVI) and the National Center for Macromolecular Imaging (NCMI) hosted a molecular animation workshop for 21 structural biologists, molecular animators, and creators of molecular visualization software. Molecular animation aims to visualize scientific understanding of biomolecular processes and structures. The primary goal of the workshop was to identify the necessary tools for: producing high quality molecular animations, understanding complex molecular and cellular structures, creating publication supplementary materials and conference presentations, and teaching science to students and the public. Another use of molecular animation emerged in the workshop: helping to focus scientific inquiry about the motions of molecules and enhancing informal communication within and between laboratories. PMID:20947014

  11. Rapid host switching in generalist Campylobacter strains erodes the signal for tracing human infections.

    PubMed

    Dearlove, Bethany L; Cody, Alison J; Pascoe, Ben; Méric, Guillaume; Wilson, Daniel J; Sheppard, Samuel K

    2016-03-01

    Campylobacter jejuni and Campylobacter coli are the biggest causes of bacterial gastroenteritis in the developed world, with human infections typically arising from zoonotic transmission associated with infected meat. Because Campylobacter is not thought to survive well outside the gut, host-associated populations are genetically isolated to varying degrees. Therefore, the likely origin of most strains can be determined by host-associated variation in the genome. This is instructive for characterizing the source of human infection. However, some common strains, notably isolates belonging to the ST-21, ST-45 and ST-828 clonal complexes, appear to have broad host ranges, hindering source attribution. Here whole-genome sequencing has the potential to reveal fine-scale genetic structure associated with host specificity. We found that rates of zoonotic transmission among animal host species in these clonal complexes were so high that the signal of host association is all but obliterated, estimating one zoonotic transmission event every 1.6, 1.8 and 12 years in the ST-21, ST-45 and ST828 complexes, respectively. We attributed 89% of clinical cases to a chicken source, 10% to cattle and 1% to pig. Our results reveal that common strains of C. jejuni and C. coli infectious to humans are adapted to a generalist lifestyle, permitting rapid transmission between different hosts. Furthermore, they show that the weak signal of host association within these complexes presents a challenge for pinpointing the source of clinical infections, underlining the view that whole-genome sequencing, powerful though it is, cannot substitute for intensive sampling of suspected transmission reservoirs.

  12. The present and future of rabies vaccine in animals.

    PubMed

    Yang, Dong-Kun; Kim, Ha-Hyun; Lee, Kyung-Woo; Song, Jae-Young

    2013-01-01

    An effective strategy for preventing rabies consists of controlling rabies in the host reservoir with vaccination. Rabies vaccine has proven to be the most effective weapon for coping with this fatal viral zoonotic disease of warm-blooded animals, including human. Natural rabies infection of an individual is always associated with exposure to rabid animals, and the duration of clinical signs can vary from days to months. The incubation period for the disease depends on the site of the bite, severity of injury, and the amount of infecting virus at the time of exposure. The mortality of untreated cases in humans is 100%. Over the last 100 years, various rabies vaccines have been developed and used to prevent or control rabies in animals, such as modified live vaccine, inactivated rabies vaccine, and oral modified live vaccine. These have proved safe and efficacious worldwide. New-generation rabies vaccines, including recombinant rabies virus-based vaccines, vectored vaccines, DNA-based vaccines, and plant vaccines, have been explored to overcome the limitations of conventional rabies vaccines. This article discusses current and next-generation rabies vaccines in animals.

  13. Detection of Cryptosporidium spp. in free ranging animals of Tehran, Iran.

    PubMed

    Mirzaghavami, Mehran; Sadraei, Javid; Forouzandeh, Mehdi

    2016-12-01

    Cryptosporidium is a world widely distributed parasite which comparatively has a high prevalence in developing countries. The zoonotic potential of some Cryptosporidium species has made the cryptosporidiosis a significant concern to physicians and veterinarians. The occurrence and zoonotic potential of Cryptosporidium species in probable reservoir hosts for man infections was determined by examining faeces of symptomatic and asymptomatic animals. The aim of this study is to screen the presence of Cryptosporidium in fecal sample of free ranging animals in Tehran using Ziehl-Neelsen staining method. The findings indicate that Cryptosporidium are present in 9/50 (18 %) stray cat (Felis catus), 12/50 (24 %) hooded crows (Corvus cornix), 23/180 (12.7 %) rat (Rattus norvegicus and R. rattus) and 1/40 (2.5 %) pigeons (Columba livia). This investigation confirms the potential role of rats, cats, crows and pigeons for zoonotic transmission of human cryptosporidiosis and they must be considered as reservoir hosts which can endanger public health.

  14. Hosts and parasites as aliens.

    PubMed

    Taraschewski, H

    2006-06-01

    Over the past decades, various free-living animals (hosts) and their parasites have invaded recipient areas in which they had not previously occurred, thus gaining the status of aliens or exotics. In general this happened to a low extent for hundreds of years. With variable frequency, invasions have been followed by the dispersal and establishment of non-indigenous species, whether host or parasite. In the literature thus far, colonizations by both hosts and parasites have not been treated and reviewed together, although both are usually interwoven in various ways. As to those factors permitting invasive success and colonization strength, various hypotheses have been put forward depending on the scientific background of respective authors and on the conspicuousness of certain invasions. Researchers who have tried to analyse characteristic developmental patterns, the speed of dispersal or the degree of genetic divergence in populations of alien species have come to different conclusions. Among parasitologists, the applied aspects of parasite invasions, such as the negative effects on economically important hosts, have long been at the centre of interest. In this contribution, invasions by hosts as well as parasites are considered comparatively, revealing many similarities and a few differences. Two helminths, the liver fluke, Fasciola hepatica, of cattle and sheep and the swimbladder nematode, Anguillicola crassus, of eels are shown to be useful as model parasites for the study of animal invasions and environmental global change. Introductions of F. hepatica have been associated with imports of cattle or other grazing animals. In various target areas, susceptible lymnaeid snails serving as intermediate hosts were either naturally present and/or were introduced from the donor continent of the parasite (Europe) and/or from other regions which were not within the original range of the parasite, partly reflecting progressive stages of a global biota change. In several

  15. Animal models of disease shed light on Nipah virus pathogenesis and transmission

    PubMed Central

    de Wit, Emmie; Munster, Vincent J.

    2014-01-01

    Nipah virus is an emerging virus infection that causes yearly disease outbreaks with high case fatality rates in Bangladesh. Nipah virus causes encephalitis and systemic vasculitis, sometimes in combination with respiratory disease. Pteropus species fruit bats are the natural reservoir of Nipah virus and zoonotic transmission can occur directly or via an intermediate host; human-to-human transmission occurs regularly. In this review we discuss the current state of knowledge on the pathogenesis and transmission of Nipah virus, focusing on dissemination of the virus through its host, known determinants of pathogenicity and routes of zoonotic and human-to-human transmission. Since data from human cases are sparse, this knowledge is largely based on the results of studies performed in animal models that recapitulate Nipah virus disease in humans. PMID:25229234

  16. Optoelectronic Reservoir Computing

    PubMed Central

    Paquot, Y.; Duport, F.; Smerieri, A.; Dambre, J.; Schrauwen, B.; Haelterman, M.; Massar, S.

    2012-01-01

    Reservoir computing is a recently introduced, highly efficient bio-inspired approach for processing time dependent data. The basic scheme of reservoir computing consists of a non linear recurrent dynamical system coupled to a single input layer and a single output layer. Within these constraints many implementations are possible. Here we report an optoelectronic implementation of reservoir computing based on a recently proposed architecture consisting of a single non linear node and a delay line. Our implementation is sufficiently fast for real time information processing. We illustrate its performance on tasks of practical importance such as nonlinear channel equalization and speech recognition, and obtain results comparable to state of the art digital implementations. PMID:22371825

  17. Natural history of Zoonotic Babesia: Role of wildlife reservoirs

    PubMed Central

    Yabsley, Michael J.; Shock, Barbara C.

    2012-01-01

    Babesiosis is an emerging zoonotic disease on all inhabited continents and various wildlife species are the principal reservoir hosts for zoonotic Babesia species. The primary vectors of Babesia are Ixodid ticks, with the majority of zoonotic species being transmitted by species in the genus Ixodes. Species of Babesia vary in their infectivity, virulence and pathogenicity for people. Various factors (e.g., increased interactions between people and the environment, increased immunosuppression, changes in landscape and climate, and shifts in host and vector species abundance and community structures) have led to an increase in tick-borne diseases in people, including babesiosis. Furthermore, because babesiosis is now a reportable disease in several states in the United States, and it is the most common blood transfusion-associated parasite, recognized infections are expected to increase. Because of the zoonotic nature of these parasites, it is essential that we understand the natural history (especially reservoirs and vectors) so that appropriate control and prevention measures can be implemented. Considerable work has been conducted on the ecology of Babesia microti and Babesia divergens, the two most common causes of babesiosis in the United States and Europe, respectively. However, unfortunately, for many of the zoonotic Babesia species, the reservoir(s) and/or tick vector(s) are unknown. We review the current knowledge regarding the ecology of Babesia among their reservoir and tick hosts with an emphasis of the role on wildlife as reservoirs. We hope to encourage the molecular characterization of Babesia from potential reservoirs and vectors as well from people. These data are necessary so that informed decisions can be made regarding potential vectors and the potential role of wildlife in the ecology of a novel Babesia when it is detected in a human patient. PMID:24533312

  18. Manicouagin Reservoir of Canada

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Recorded by the Space Shuttle Atlantis STS-110 mission, this is a photograph of the ice- covered Manicouagin Reservoir located in the Canadian Shield of Quebec Province in Eastern Canada, partially obscured by low clouds. This reservoir marks the site of an impact crater, 60 miles (100 kilometers) wide, which according to geologists was formed 212 million years ago when a meteorite crashed into this area. Over millions of years, the crater has been worn down by glaciers and other erosional processes. The Space Shuttle Orbiter Atlantis, STS-110 mission, was launched April 8, 2002 and returned to Earth April 19, 2002.

  19. Animal Bites

    MedlinePlus

    Wild animals usually avoid people. They might attack, however, if they feel threatened, are sick, or are protecting their ... or territory. Attacks by pets are more common. Animal bites rarely are life-threatening, but if they ...

  20. Mycobacterium tuberculosis and the host response

    PubMed Central

    Kaufmann, Stefan H.E.; Cole, Stewart T.; Mizrahi, Valerie; Rubin, Eric; Nathan, Carl

    2005-01-01

    Mycobacterium tuberculosis remains a leading cause of morbidity and mortality worldwide. Advances reported at a recent international meeting highlight insights and controversies in the genetics of M. tuberculosis and the infected host, the nature of protective immune responses, adaptation of the bacillus to host-imposed stresses, animal models, and new techniques. PMID:15939785

  1. Reservoir stability studies

    SciTech Connect

    Doherty, T.J.

    1981-07-01

    The objective of the reservoir stability studies project is to develop stability criteria for large underground reservoirs in salt domes, hard rock caverns, and porous rock structures for air storage in utility applications. Because reservoir stability was deemed crucial to commercialization of compressed air energy storage (CAES) systems this project has received major emphasis in the early phases of the overall CAES program. A long term plan, including state-of-the-art assessment, numerical model development and experimental studies culminating in field research, as necessary, was formulated. This plan, initiated in 1977, has been completed during FY-1981 to the stage of specific experimental studies and field research. Activities within this project during FY-1981 have included completion of site specific geotechnical design evaluations using methodologies developed to assess hard rock cavern stability, implementation of in-mine research to evaluate numerical and laboratory study conclusions on the response of domal salt, and preparation of integrated laboratory and field study facilities to assess developed predictive methods and determine in situ response of a porous media reservoir to air injection. The major activity in the project has been the field study component of the porous media studies. Accomplishments there have included completion of exploration, permitting and leasing, operation contractor selection and negotiation, and initiation of procurement and construction for an FY-1982 test initiation. A major program milestone, drilling of the injection withdrawal well for this test, was completed ahead of schedule.

  2. Applying reservoir characterization technology

    SciTech Connect

    Lake, L.W.

    1994-12-31

    While reservoir characterization is an old discipline, only within the last 10 years have engineers and scientists been able to make quantitative descriptions, due mostly to improvements in high-resolution computational power, sophisticated graphics, and geostatistics. This paper summarizes what has been learned during the past decade by using these technologies.

  3. Reinjection into geothermal reservoirs

    SciTech Connect

    Bodvarsson, G.S.; Stefansson, V.

    1987-08-01

    Reinjection of geothermal wastewater is practiced as a means of disposal and for reservoir pressure support. Various aspects of reinjection are discussed, both in terms of theoretical studies as well as specific field examples. The discussion focuses on the major effects of reinjection, including pressure maintenance and chemical and thermal effects. (ACR)

  4. Ticks collected from humans, domestic animals, and wildlife in Yucatan, Mexico.

    PubMed

    Rodríguez-Vivas, R I; Apanaskevich, D A; Ojeda-Chi, M M; Trinidad-Martínez, I; Reyes-Novelo, E; Esteve-Gassent, M D; Pérez de León, A A

    2016-01-15

    Domestic animals and wildlife play important roles as reservoirs of zoonotic pathogens that are transmitted to humans by ticks. Besides their role as vectors of several classes of microorganisms of veterinary and public health relevance, ticks also burden human and animal populations through their obligate blood-feeding habit. It is estimated that in Mexico there are around 100 tick species belonging to the Ixodidae and Argasidae families. Information is lacking on tick species that affect humans, domestic animals, and wildlife through their life cycle. This study was conducted to bridge that knowledge gap by inventorying tick species that infest humans, domestic animals and wildlife in the State of Yucatan, Mexico. Amblyomma ticks were observed as euryxenous vertebrate parasites because they were found parasitizing 17 animal species and human. Amblyomma mixtum was the most eryxenous species found in 11 different animal species and humans. Both A. mixtum and A. parvum were found parasitizing humans. Ixodes near affinis was the second most abundant species parasitizing six animal species (dogs, cats, horses, white-nosed coati, white-tail deer and black vulture) and was found widely across the State of Yucatan. Ixodid tick populations may increase in the State of Yucatan with time due to animal production intensification, an increasing wildlife population near rural communities because of natural habitat reduction and fragmentation. The diversity of ticks across host taxa documented here highlights the relevance of ecological information to understand tick-host dynamics. This knowledge is critical to inform public health and veterinary programs for the sustainable control of ticks and tick-borne diseases.

  5. A systematic review and meta-analysis of the epidemiology of pathogenic Escherichia coli of calves and the role of calves as reservoirs for human pathogenic E. coli.

    PubMed

    Kolenda, Rafał; Burdukiewicz, Michał; Schierack, Peter

    2015-01-01

    Escherichia coli bacteria are the most common causes of diarrhea and septicemia in calves. Moreover, calves form a major reservoir for transmission of pathogenic E. coli to humans. Systematic reviews and meta-analyses of publications on E. coli as calf pathogens and the role of calves as reservoir have not been done so far. We reviewed studies between 1951 and 2013 reporting the presence of virulence associated factors (VAFs) in calf E. coli and extracted the following information: year(s) and country of sampling, animal number, health status, isolate number, VAF prevalence, serotypes, diagnostic methods, and biological assays. The prevalence of VAFs or E. coli pathotypes was compared between healthy and diarrheic animals and was analyzed for time courses. Together, 106 papers with 25,982 E. coli isolates from 27 countries tested for VAFs were included. F5, F17, and F41 fimbriae and heat-stable enterotoxin (ST) - VAFs of enterotoxigenic E. coli (ETEC) were significantly associated with calf diarrhea. On the contrary, ETEC VAF F4 fimbriae and heat-labile enterotoxin as well as enteropathogenic (EPEC), Shiga toxin-producing (STEC), and enterohemorrhagic E. coli (EHEC) were not associated with diarrhea. The prevalence increased overtime for ST-positive isolates, but decreased for F5- and STEC-positive isolates. Our study provides useful information about the history of scientific investigations performed in this domain so far, and helps to define etiological agents of calf disease, and to evaluate calves as reservoir hosts for human pathogenic E. coli.

  6. First report of natural infection in hedgehogs with Leishmania major, a possible reservoir of zoonotic cutaneous leishmaniasis in Algeria.

    PubMed

    Tomás-Pérez, Míriam; Khaldi, Mourad; Riera, Cristina; Mozo-León, Denis; Ribas, Alexis; Hide, Mallorie; Barech, Ghania; Benyettou, Meryam; Seghiri, Kamel; Doudou, Souad; Fisa, Roser

    2014-07-01

    We report here the first known cases of natural infection of hedgehogs with Leishmania major. Cutaneous leishmaniasis is an important public health problem in the area of M'sila, a semi-arid province in Algeria's northern Sahara, where two species of hedgehog live, Atelerix algirus and Paraechinus aethiopicus. The aim of this research was to survey Leishmania infection in these hedgehogs and evaluate whether they were reservoir hosts of Leishmania in an endemic zoonotic focus of leishmaniasis. Serological and molecular methods were used to determine the presence of Leishmania in 24 hedgehogs caught directly by hand and identified at species level as 19 A. algirus and 5 P. aethiopicus. Specific anti-Leishmania antibodies were detected in 29.2% of individuals by Western blot and in 26.3% by ELISA. The real-time PCR performed in spleen, ear and blood samples detected Leishmania spp. DNA in 12.5% of the individuals, one A. algirus and two P. aethiopicus. Three skin and two spleen samples of these animals were found to be parasitized and were identified by molecular test as L. major. Considering our results, it is suggested that hedgehogs have a potential epidemiological role as reservoir hosts of L. major.

  7. Molecular characterization of Giardia intestinalis haplotypes in marine animals: variation and zoonotic potential.

    PubMed

    Lasek-Nesselquist, Erica; Bogomolni, Andrea L; Gast, Rebecca J; Welch, David Mark; Ellis, Julie C; Sogin, Mitchell L; Moore, Michael J

    2008-08-19

    Giardia intestinalis is a microbial eukaryotic parasite that causes diarrheal disease in humans and other vertebrates worldwide. The negative effect on quality of life and economics caused by G. intestinalis may be increased by its potential status as a zoonosis, or a disease that can be transmitted from animals to humans. The zoonotic potential of G. intestinalis has been implied for over 2 decades, with human-infecting genotypes (belonging to the 2 major subgroups, Assemblages A and B) occurring in wildlife and domesticated animals. There are recent reports of G. intestinalis in shellfish, seals, sea lions and whales, suggesting that marine animals are also potential reservoirs of human disease. However, the prevalence, genetic diversity and effect of G. intestinalis in marine environments and the role that marine animals play in transmission of this parasite to humans are relatively unexplored. Here, we provide the first thorough molecular characterization of G. intestinalis in marine vertebrates. Using a multi-locus sequencing approach, we identify human-infecting G. intestinalis haplotypes of both Assemblages A and B in the fecal material of dolphins, porpoises, seals, herring gulls Larus argentatus, common eiders Somateria mollissima and a thresher shark Alopias vulpinus. Our results indicate that G. intestinalis is prevalent in marine ecosystems, and a wide range of marine hosts capable of harboring zoonotic forms of this parasite exist. The presence of G. intestinalis in marine ecosystems raises concerns about how this disease might be transmitted among different host species.

  8. Development of animal models against emerging coronaviruses: From SARS to MERS coronavirus.

    PubMed

    Sutton, Troy C; Subbarao, Kanta

    2015-05-01

    Two novel coronaviruses have emerged to cause severe disease in humans. While bats may be the primary reservoir for both viruses, SARS coronavirus (SARS-CoV) likely crossed into humans from civets in China, and MERS coronavirus (MERS-CoV) has been transmitted from camels in the Middle East. Unlike SARS-CoV that resolved within a year, continued introductions of MERS-CoV present an on-going public health threat. Animal models are needed to evaluate countermeasures against emerging viruses. With SARS-CoV, several animal species were permissive to infection. In contrast, most laboratory animals are refractory or only semi-permissive to infection with MERS-CoV. This host-range restriction is largely determined by sequence heterogeneity in the MERS-CoV receptor. We describe animal models developed to study coronaviruses, with a focus on host-range restriction at the level of the viral receptor and discuss approaches to consider in developing a model to evaluate countermeasures against MERS-CoV.

  9. Dynamic-reservoir lubricating device

    NASA Technical Reports Server (NTRS)

    Ficken, W. H.; Schulien, H. E.

    1968-01-01

    Dynamic-reservoir lubricating device supplies controlled amounts of lubricating oil to ball bearings during operation of the bearings. The dynamic reservoir lubricating device includes a rotating reservoir nut, a hollow cylinder filled with lubricating oil, flow restrictors and a ball bearing retainer.

  10. Entry, Descent, Landing Animation (Animation)

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Click on the image for Entry, Descent, Landing animation

    This animation illustrates the path the Stardust return capsule will follow once it enters Earth's atmosphere.

  11. Are ticks venomous animals?

    PubMed Central

    2014-01-01

    Introduction As an ecological adaptation venoms have evolved independently in several species of Metazoa. As haematophagous arthropods ticks are mainly considered as ectoparasites due to directly feeding on the skin of animal hosts. Ticks are of major importance since they serve as vectors for several diseases affecting humans and livestock animals. Ticks are rarely considered as venomous animals despite that tick saliva contains several protein families present in venomous taxa and that many Ixodida genera can induce paralysis and other types of toxicoses. Tick saliva was previously proposed as a special kind of venom since tick venom is used for blood feeding that counteracts host defense mechanisms. As a result, the present study provides evidence to reconsider the venomous properties of tick saliva. Results Based on our extensive literature mining and in silico research, we demonstrate that ticks share several similarities with other venomous taxa. Many tick salivary protein families and their previously described functions are homologous to proteins found in scorpion, spider, snake, platypus and bee venoms. This infers that there is a structural and functional convergence between several molecular components in tick saliva and the venoms from other recognized venomous taxa. We also highlight the fact that the immune response against tick saliva and venoms (from recognized venomous taxa) are both dominated by an allergic immunity background. Furthermore, by comparing the major molecular components of human saliva, as an example of a non-venomous animal, with that of ticks we find evidence that ticks resemble more venomous than non-venomous animals. Finally, we introduce our considerations regarding the evolution of venoms in Arachnida. Conclusions Taking into account the composition of tick saliva, the venomous functions that ticks have while interacting with their hosts, and the distinguishable differences between human (non-venomous) and tick salivary

  12. An investigation into alternative reservoirs of canine leishmaniasis on the endemic island of Mallorca (Spain).

    PubMed

    Millán, J; Zanet, S; Gomis, M; Trisciuoglio, A; Negre, N; Ferroglio, E

    2011-08-01

    The role of wild and free-roaming domestic carnivores as a reservoir of Leishmania infantum was investigated on the Mediterranean island of Mallorca (Balearic Islands, Spain), an endemic area for this disease. Serum, blood and/or spleen samples from 169 animals [48 dogs from a kennel, 86 wild-caught feral cats, 23 pine martens (Martes martes), 10 common genets (Genetta genetta) and two weasels (Mustela nivalis)] were analysed. Seroprevalence determined by Western blotting was 38% in dogs and 16% in feral cats, while the prevalence of infection determined by PCR was 44% in dogs, 26% in cats, 39% in pine martens and 10% in genets. This is the first report of infection by L. infantum in the pine marten or any other member of the Mustelidae family. Restriction fragment length polymorphism (RFLP) analysis found 33 different patterns in 23 dogs, 14 cats and three martens. Two patterns were shared by dogs and cats, two by different cats, and one by different dogs. Patterns were different to those previously reported in carnivores from peninsular Spain. No external lesions compatible with leishmaniasis were observed in any species other than the dogs. Although the dog is probably the primary reservoir of leishmaniasis in endemic areas, the prevalence and the absence of apparent signs of this disease within the island's abundant feral cat and pine marten populations could make these species potential primary or secondary hosts of L. infantum in Mallorca.

  13. Dermatophytoses in animals.

    PubMed

    Chermette, René; Ferreiro, Laerte; Guillot, Jacques

    2008-01-01

    Dermatophytoses are one of the most frequent skin diseases of pets and livestock. Contagiousness among animal communities, high cost of treatment, difficulty of control measures, and the public health consequences of animal ringworm explain their great importance. A wide variety of dermatophytes have been isolated from animals, but a few zoophilic species are responsible for the majority of the cases, viz. Microsporum canis, Trichophyton mentagrophytes, Trichophyton equinum and Trichophyton verrucosum, as also the geophilic species Microsporum gypseum. According to the host and the fungal species involved, the typical aspect of dermatophytic lesions may be modified. As a consequence, an accurate clinical examination, a good differential diagnosis and laboratory analyses are required for a correct identification. Few antifungal agents are available and licenced for use in veterinary practice, and the use of systemic drugs is limited in livestock due to the problems of residues in products intended for human consumption. The high resistance of the dermatophyte arthroconidia in the environment, the multiplicity of host species, and the confinement of animals in breedings are cause of an enzootic situation in many cases. Prevention is difficult, but research development on the immune response to dermatophytes and the use of vaccination, especially in cattle, have brought some interesting results.

  14. Status of Blue Ridge Reservoir

    SciTech Connect

    Not Available

    1990-09-01

    This is one in a series of reports prepared by the Tennessee Valley Authority (TVA) for those interested in the conditions of TVA reservoirs. This overview of Blue Ridge Reservoir summarizes reservoir and watershed characteristics, reservoir uses and use impairments, water quality and aquatic biological conditions, and activities of reservoir management agencies. This information was extracted from the most current reports and data available, as well as interview with water resource professionals in various federal, state, and local agencies. Blue Ridge Reservoir is a single-purpose hydropower generating project. When consistent with this primary objective, the reservoir is also operated to benefit secondary objectives including water quality, recreation, fish and aquatic habitat, development of shoreline, aesthetic quality, and other public and private uses that support overall regional economic growth and development. 8 refs., 1 fig.

  15. Interactive reservoir simulation

    SciTech Connect

    Regtien, J.M.M. Por, G.J.A.; Stiphout, M.T. van; Vlugt, F.F. van der

    1995-12-31

    Shell`s new Modular Reservoir Simulator (MoReS) has been equipped with a comprehensive and versatile user interface called FrontEnd. Apart from providing a user-friendly environment for interactive reservoir simulation, FrontEnd serves a software platform for other dynamic simulation and reservoir-engineering applications. It offers to all supported applications a common user interface, enables the re-use of code and reduces overall maintenance and support costs associated with the embedded applications. Because of its features, FrontEnd facilitates the transfer of research results in the form of operational software to end users. When coupled with MoReS, FrontEnd can be used for pre- and post-processing and interactive simulation. The pre-processing options allow data to be inputted by means of various OSF/Motif widgets containing a spreadsheet, text editors, dialogues and graphical input. The display of the input data as well as the post-processing of all simulation results is made possible by a variety of user-defined plot of tabular (e.g. timestep summary) and array (simulation grid) data. During a simulation user-defined plots can be displayed and edited, allowing a close inspection of the results as they are being calculated. FrontEnd has been equipped with a powerful input command language, which gives the batch user as much flexibility and control over the input as the interactive user.

  16. MEDLI Animation

    NASA Video Gallery

    Animation of MEDLI, the Mars Science Laboratory Entry, Descent, and Landing Instrument, which contains multiple sophisticated temperature sensors to measure atmospheric conditions and performance o...

  17. Avian host defense peptides.

    PubMed

    Cuperus, Tryntsje; Coorens, Maarten; van Dijk, Albert; Haagsman, Henk P

    2013-11-01

    Host defense peptides (HDPs) are important effector molecules of the innate immune system of vertebrates. These antimicrobial peptides are also present in invertebrates, plants and fungi. HDPs display broad-spectrum antimicrobial activities and fulfill an important role in the first line of defense of many organisms. It is becoming increasingly clear that in the animal kingdom the functions of HDPs are not confined to direct antimicrobial actions. Research in mammals has indicated that HDPs have many immunomodulatory functions and are also involved in other physiological processes ranging from development to wound healing. During the past five years our knowledge about avian HDPs has increased considerably. This review addresses our current knowledge on the evolution, regulation and biological functions of HDPs of birds.

  18. Henipaviruses: an updated review focusing on the pteropid reservoir and features of transmission.

    PubMed

    Clayton, B A; Wang, L F; Marsh, G A

    2013-02-01

    The henipaviruses, Hendra virus and Nipah virus, are pathogens that have emerged from flying foxes in Australia and South-east Asia to infect both livestock and humans, often fatally. Since the emergence of Hendra virus in Australia in 1994 and the identification of Australian flying foxes as hosts to this virus, our appreciation of bats as reservoir hosts of henipaviruses has expanded globally to include much of Asia and areas of Africa. Despite this, little is currently known of the mechanisms by which bats harbour viruses capable of causing such severe disease in other terrestrial mammals. Pteropid bat ecology, henipavirus virology, therapeutic developments and features of henipavirus infection, pathology and disease in humans and other mammals are reviewed elsewhere in detail. This review focuses on bats as reservoir hosts to henipaviruses and features of transmission of Hendra virus and Nipah virus following spillover from these reservoir hosts.

  19. Multilocus sequence analysis of Anaplasma phagocytophilum reveals three distinct lineages with different host ranges in clinically ill French cattle.

    PubMed

    Chastagner, Amélie; Dugat, Thibaud; Vourc'h, Gwenaël; Verheyden, Hélène; Legrand, Loïc; Bachy, Véronique; Chabanne, Luc; Joncour, Guy; Maillard, Renaud; Boulouis, Henri-Jean; Haddad, Nadia; Bailly, Xavier; Leblond, Agnès

    2014-12-09

    Molecular epidemiology represents a powerful approach to elucidate the complex epidemiological cycles of multi-host pathogens, such as Anaplasma phagocytophilum. A. phagocytophilum is a tick-borne bacterium that affects a wide range of wild and domesticated animals. Here, we characterized its genetic diversity in populations of French cattle; we then compared the observed genotypes with those found in horses, dogs, and roe deer to determine whether genotypes of A. phagocytophilum are shared among different hosts. We sampled 120 domesticated animals (104 cattle, 13 horses, and 3 dogs) and 40 wild animals (roe deer) and used multilocus sequence analysis on nine loci (ankA, msp4, groESL, typA, pled, gyrA, recG, polA, and an intergenic region) to characterize the genotypes of A. phagocytophilum present. Phylogenic analysis revealed three genetic clusters of bacterial variants in domesticated animals. The two principal clusters included 98% of the bacterial genotypes found in cattle, which were only distantly related to those in roe deer. One cluster comprised only cattle genotypes, while the second contained genotypes from cattle, horses, and dogs. The third contained all roe deer genotypes and three cattle genotypes. Geographical factors could not explain this clustering pattern. These results suggest that roe deer do not contribute to the spread of A. phagocytophilum in cattle in France. Further studies should explore if these different clusters are associated with differing disease severity in domesticated hosts. Additionally, it remains to be seen if the three clusters of A. phagocytophilum genotypes in cattle correspond to distinct epidemiological cycles, potentially involving different reservoir hosts.

  20. ANIMAL MODELS FOR THE STUDY OF LEISHMANIASIS IMMUNOLOGY

    PubMed Central

    Loría-Cervera, Elsy Nalleli; Andrade-Narváez, Fernando José

    2014-01-01

    Leishmaniasis remains a major public health problem worldwide and is classified as Category I by the TDR/WHO, mainly due to the absence of control. Many experimental models like rodents, dogs and monkeys have been developed, each with specific features, in order to characterize the immune response to Leishmania species, but none reproduces the pathology observed in human disease. Conflicting data may arise in part because different parasite strains or species are being examined, different tissue targets (mice footpad, ear, or base of tail) are being infected, and different numbers (“low” 1×102 and “high” 1×106) of metacyclic promastigotes have been inoculated. Recently, new approaches have been proposed to provide more meaningful data regarding the host response and pathogenesis that parallels human disease. The use of sand fly saliva and low numbers of parasites in experimental infections has led to mimic natural transmission and find new molecules and immune mechanisms which should be considered when designing vaccines and control strategies. Moreover, the use of wild rodents as experimental models has been proposed as a good alternative for studying the host-pathogen relationships and for testing candidate vaccines. To date, using natural reservoirs to study Leishmania infection has been challenging because immunologic reagents for use in wild rodents are lacking. This review discusses the principal immunological findings against Leishmania infection in different animal models highlighting the importance of using experimental conditions similar to natural transmission and reservoir species as experimental models to study the immunopathology of the disease. PMID:24553602

  1. Kindergarten Animation

    ERIC Educational Resources Information Center

    Hinshaw, Craig

    2012-01-01

    Animation is one of the last lessons that come to mind when thinking of kindergarten art. The necessary understanding of sequencing, attention to small, often detailed drawings, and the use of technology all seem more suitable to upper elementary. With today's emphasis on condensing and integrating curriculum, consider developing animation lessons…

  2. Excelsior Animals.

    ERIC Educational Resources Information Center

    Steinkamp, Mary J.

    2001-01-01

    Describes an art project where students used excelsior, shredded wood used for packing, to create animals. Explains that excelsior can be found at furniture and grocery stores. Discusses in detail the process of making the animals and includes learning objectives. (CMK)

  3. Animal Detectives

    ERIC Educational Resources Information Center

    Mulvey, Bridget; Warnock, Carly

    2015-01-01

    During a two-week inquiry-based 5E learning cycle unit, children made observations and inferences to guide their explorations of animal traits and habitats (Bybee 2014). The children became "animal detectives" by studying a live-feed webcam and digital images of wolves in their natural habitat, reading books and online sources about…

  4. Animal Allies.

    ERIC Educational Resources Information Center

    Peterson, Brenda

    1999-01-01

    Discusses young teenagers' adoption of animal personas in their creative writing classes, and the way these classroom activities follow Montessori principles. Considers both the role of imagination in the animal identification and the psychological and pedagogical significance of the underlying development of unconscious kinship with Earth and its…

  5. Chicken as Reservoir for Extraintestinal Pathogenic Escherichia coli in Humans, Canada

    PubMed Central

    Bergeron, Catherine Racicot; Prussing, Catharine; Boerlin, Patrick; Daignault, Danielle; Dutil, Lucie; Reid-Smith, Richard J.; Zhanel, George G.

    2012-01-01

    We previously described how retail meat, particularly chicken, might be a reservoir for extraintestinal pathogenic Escherichia coli (ExPEC) causing urinary tract infections (UTIs) in humans. To rule out retail beef and pork as potential reservoirs, we tested 320 additional E. coli isolates from these meats. Isolates from beef and pork were significantly less likely than those from chicken to be genetically related to isolates from humans with UTIs. We then tested whether the reservoir for ExPEC in humans could be food animals themselves by comparing geographically and temporally matched E. coli isolates from 475 humans with UTIs and from cecal contents of 349 slaughtered animals. We found genetic similarities between E. coli from animals in abattoirs, principally chickens, and ExPEC causing UTIs in humans. ExPEC transmission from food animals could be responsible for human infections, and chickens are the most probable reservoir. PMID:22377351

  6. Reservoirs of Non-baumannii Acinetobacter Species

    PubMed Central

    Al Atrouni, Ahmad; Joly-Guillou, Marie-Laure; Hamze, Monzer; Kempf, Marie

    2016-01-01

    Acinetobacter spp. are ubiquitous gram negative and non-fermenting coccobacilli that have the ability to occupy several ecological niches including environment, animals and human. Among the different species, Acinetobacter baumannii has evolved as global pathogen causing wide range of infection. Since the implementation of molecular techniques, the habitat and the role of non-baumannii Acinetobacter in human infection have been elucidated. In addition, several new species have been described. In the present review, we summarize the recent data about the natural reservoir of non-baumannii Acinetobacter including the novel species that have been described for the first time from environmental sources and reported during the last years. PMID:26870013

  7. 42 CFR 71.54 - Etiological agents, hosts, and vectors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... any arthropod or other animal host or vector of human disease, or any exotic living arthropod or other animal capable of being a host or vector of human disease unless accompanied by a permit issued by the... Section 71.54 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  8. 42 CFR 71.54 - Etiological agents, hosts, and vectors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... any arthropod or other animal host or vector of human disease, or any exotic living arthropod or other animal capable of being a host or vector of human disease unless accompanied by a permit issued by the... Section 71.54 Public Health PUBLIC HEALTH SERVICE, DEPARTMENT OF HEALTH AND HUMAN SERVICES...

  9. Sedimentological characterization of braided and meandering fluvial reservoirs: Prediction of size and heterogeneity

    SciTech Connect

    Davies, D.K. ); Vargas, J. )

    1993-02-01

    Fluvial reservoirs host significant volumes of hydrocarbons. They comprise a significant reserve base in areas and formations as diverse as the San Jorge Basin, Argentina, the Lagunillas Formation, Venezuela, and Cano Limon Field, Colombia. Effective development and reservoir management required detailed sedimentological characterization because fluvial reservoirs, irrespective of age and geographic location, are characterized by considerable variability in geometry and internal heterogeneity. This paper presents models of braided and meandering reservoirs in selected Tertiary and Cretaceous fields of South and North America, based on sedimentological characterization using conventional cores and wireline logs. Fieldwide (macro-scale) and inter-well (meso-scale) heterogeneity is determined through detailed evaluation of facies distribution, particularly the distribution and maturity of paleosol horizons (e.g. calcretes). Within a given reservoir, micro-scale variations in porosity, permeability and saturation are fundamentally related to depositional environment. Effective permeability to hydrocarbons varies with environment and bedding style. The size of meandering and braided channel reservoirs is predicted using empirical geological equations. Predicted dimensions are compared with the independent results of reservoir simulation analysis for the same sand bodies. Engineering and sedimentological predictions of reservoir size and heterogeneity are similar, particularly in reservoirs where median permeability to hydrocarbons is > 1 md. The size and heterogeneity of productive channel reservoirs can be predicted at an early stage in field development is channel style and channel depth are known. Determination of these two fundamental parameters required sedimentological characterization at the macro-, meso-, and micro-scale using wireline logs and cores.

  10. Assessing contribution of DOC from sediments to a drinking-water reservoir using optical profiling

    USGS Publications Warehouse

    Downing, Bryan D.; Bergamaschi, Brian A.; Evans, David G.; Boss, Emmanuel

    2008-01-01

    Understanding the sources of dissolved organic carbon (DOC) in drinking-water reservoirs is an important management issue because DOC may form disinfection by-products, interfere with disinfection, or increase treatment costs. DOC may be derived from a host of sources-algal production of DOC in the reservoir, marginal production of DOC from mucks and vascular plants at the margins, and sediments in the reservoir. The purpose of this study was to assess if release of DOC from reservoir sediments containing ferric chloride coagulant was a significant source of DOC to the reservoir. We examined the source-specific contributions of DOC using a profiling system to measure the in situ distribution of optical properties of absorption and fluorescence at various locations in the reservoir. Vertical optical profiles were coupled with discrete water samples measured in the laboratory for DOC concentration and optical properties: absorption spectra and excitation emission matrix spectra (EEMs). Modeling the in situ optical data permitted estimation of the bulk DOC profile in the reservoir as well as separation into source-specific contributions. Analysis of the source-specific profiles and their associated optical characteristics indicated that the sedimentary source of DOC to the reservoir is significant and that this DOC is labile in the reservoir. We conclude that optical profiling is a useful technique for understanding complex biogeochemical processes in a reservoir.

  11. 42 CFR 71.54 - Etiological agents, hosts, and vectors.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 42 Public Health 1 2010-10-01 2010-10-01 false Etiological agents, hosts, and vectors. 71.54..., INSPECTION, LICENSING FOREIGN QUARANTINE Importations § 71.54 Etiological agents, hosts, and vectors. (a) A... any arthropod or other animal host or vector of human disease, or any exotic living arthropod or...

  12. Animal Models of Bacterial Keratitis

    PubMed Central

    Marquart, Mary E.

    2011-01-01

    Bacterial keratitis is a disease of the cornea characterized by pain, redness, inflammation, and opacity. Common causes of this disease are Pseudomonas aeruginosa and Staphylococcus aureus. Animal models of keratitis have been used to elucidate both the bacterial factors and the host inflammatory response involved in the disease. Reviewed herein are animal models of bacterial keratitis and some of the key findings in the last several decades. PMID:21274270

  13. Animal experimentation.

    PubMed

    Kolar, Roman

    2006-01-01

    Millions of animals are used every year in often times extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the "3Rs" concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. The licensing of animal experiments normally requires an ethical evaluation process, often times undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees' members. There is an ongoing societal debate about ethical issues of animal use in science. Existing EU legislation on animal experimentation for cosmetics testing is an example of both the public will for setting clear limits to animal experiments and the need to further critically examine other fields and aspects of animal experimentation.

  14. Fractured petroleum reservoirs

    SciTech Connect

    Firoozabadi, A.; Chang, E.; Tang, G.Q.

    2000-01-10

    Total compressibility in a fractured reservoir is estimated using the pressure response due to gravitational potential variations. Both the moon and the sun gravitational potentials are accounted for using the full expression by inclusion of longer-period components. The semi-diurnal and diurnal pressure data show substantial long-term variations. The gravitational potential also contains the same variation trend; the ratio between the potential and pressure has a fairly uniform value over successive cycles. The computed total compressibility is also fairly constant and independent of the cycle. Results show the effects of the time interval over which the pressure measurements are performed as well as the location.

  15. Calderas and magma reservoirs

    NASA Astrophysics Data System (ADS)

    Cashman, Katharine V.; Giordano, Guido

    2014-11-01

    Large caldera-forming eruptions have long been a focus of both petrological and volcanological studies; petrologists have used the eruptive products to probe conditions of magma storage (and thus processes that drive magma evolution), while volcanologists have used them to study the conditions under which large volumes of magma are transported to, and emplaced on, the Earth's surface. Traditionally, both groups have worked on the assumption that eruptible magma is stored within a single long-lived melt body. Over the past decade, however, advances in analytical techniques have provided new views of magma storage regions, many of which provide evidence of multiple melt lenses feeding a single eruption, and/or rapid pre-eruptive assembly of large volumes of melt. These new petrological views of magmatic systems have not yet been fully integrated into volcanological perspectives of caldera-forming eruptions. Here we explore the implications of complex magma reservoir configurations for eruption dynamics and caldera formation. We first examine mafic systems, where stacked-sill models have long been invoked but which rarely produce explosive eruptions. An exception is the 2010 eruption of Eyjafjallajökull volcano, Iceland, where seismic and petrologic data show that multiple sills at different depths fed a multi-phase (explosive and effusive) eruption. Extension of this concept to larger mafic caldera-forming systems suggests a mechanism to explain many of their unusual features, including their protracted explosivity, spatially variable compositions and pronounced intra-eruptive pauses. We then review studies of more common intermediate and silicic caldera-forming systems to examine inferred conditions of magma storage, time scales of melt accumulation, eruption triggers, eruption dynamics and caldera collapse. By compiling data from large and small, and crystal-rich and crystal-poor, events, we compare eruptions that are well explained by simple evacuation of a zoned

  16. Encapsulated microsensors for reservoir interrogation

    DOEpatents

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.

    2016-03-08

    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  17. Reservoir management cost-cutting

    SciTech Connect

    Gulati, M.S.

    1996-12-31

    This article by Mohinder S. Gulati, Chief Engineer, Unocal Geothermal Operations, discusses cost cutting in geothermal reservoir management. The reservoir engineer or geoscientist can make a big difference in the economical outcome of a project by improving well performance and thus making geothermal energy more competitive in the energy marketplace. Bringing plants online in less time and proving resources to reduce the cycle time are some of the ways to reduce reservoir management costs discussed in this article.

  18. ANIMAL ENTEROTOXIGENIC ESCHERICHIA COLI

    PubMed Central

    Dubreuil, J. Daniel; Isaacson, Richard E.; Schifferli, Dieter M.

    2016-01-01

    Enterotoxigenic Escherichia coli (ETEC) is the most common cause of E. coli diarrhea in farm animals. ETEC are characterized by the ability to produce two types of virulence factors; adhesins that promote binding to specific enterocyte receptors for intestinal colonization and enterotoxins responsible for fluid secretion. The best-characterized adhesins are expressed in the context of fimbriae, such as the F4 (also designated K88), F5 (K99), F6 (987P), F17 and F18 fimbriae. Once established in the animal small intestine, ETEC produces enterotoxin(s) that lead to diarrhea. The enterotoxins belong to two major classes; heat-labile toxin that consist of one active and five binding subunits (LT), and heat-stable toxins that are small polypeptides (STa, STb, and EAST1). This chapter describes the disease and pathogenesis of animal ETEC, the corresponding virulence genes and protein products of these bacteria, their regulation and targets in animal hosts, as well as mechanisms of action. Furthermore, vaccines, inhibitors, probiotics and the identification of potential new targets identified by genomics are presented in the context of animal ETEC. PMID:27735786

  19. The wild boar (Sus scrofa Linnaeus, 1758) as secondary reservoir of Fasciola hepatica in Galicia (NW Spain).

    PubMed

    Mezo, Mercedes; González-Warleta, Marta; Castro-Hermida, José Antonio; Manga-González, M Yolanda; Peixoto, Raquel; Mas-Coma, Santiago; Valero, M Adela

    2013-12-06

    Fasciolosis is an emerging or reemerging human and animal disease in numerous parts of the world. In Galicia (NW, Spain), the wild boar (Sus scrofa) is the main wild ungulate in terms of abundance and distribution. Its population has continuously increased over the past decades and this population growth has been accompanied by a reduction of habitats, so that the wild boar populations encroach more and more frequently onto agricultural lands. The increase of the interface area between livestock and the wild boars frequently involves the sharing of pastures and water sources, so that the circulation of common pathogens is propitiated. This is the first report concerning the importance of the wild boar as a possible reservoir of Fasciola hepatica infection in Spain. Livers from 358 hunted wild boars were analyzed showing that 11.2% were parasitized by F. hepatica, with burdens ranging from 1 to 14 flukes (mean=2.3). Fecal analysis demonstrated that 40.0% of parasitized animals shed F. hepatica eggs with a mean excretion of 6.1 eggs per gram of feces (epg). The presence of coproantigens analyzed by MM3-COPRO ELISA was positive in 62.9% of infected wild boars. After incubation, the percentage of hatched eggs ranged between 41.0% and 90.0% suggesting that the wild boar is very likely to contribute to the environmental contamination with viable parasite eggs. Comparative morphometric data were obtained using a computer image analysis system (CIAS) on the basis of standardized measurements. F. hepatica from cattle, sheep and wild boars from the same geographical area presents a similar body development and gravidity. Our study shows for the first time that the F. hepatica uterus from the wild boar presents an intermediate size between that found in primary reservoir hosts such as cattle and sheep, i.e., the individual potential egg output capacity of the wild boar does not greatly differ from that detected in Galician livestock. These results show that F. hepatica in

  20. Persistent HIV-1 replication maintains the tissue reservoir during therapy

    PubMed Central

    Bedford, Trevor; Kim, Eun-Young; Archer, John; Pond, Sergei L. Kosakovsky; Chung, Yoon-Seok; Penugonda, Sudhir; Chipman, Jeffrey; Fletcher, Courtney V.; Schacker, Timothy W.; Malim, Michael H.; Rambaut, Andrew; Haase, Ashley T.; McLean, Angela R.; Wolinsky, Steven M.

    2015-01-01

    Lymphoid tissue is a key reservoir established by HIV-1 during acute infection. It is a site of viral production, storage of viral particles in immune complexes, and viral persistence. Whilst combinations of antiretroviral drugs usually suppress viral replication and reduce viral RNA to undetectable levels in blood, it is unclear whether treatment fully suppresses viral replication in lymphoid tissue reservoirs. Here we show that virus evolution and trafficking between tissue compartments continues in patients with undetectable levels of virus in their bloodstream. A spatial dynamic model of persistent viral replication and spread explains why the development of drug resistance is not a foregone conclusion under conditions where drug concentrations are insufficient to completely block virus replication. These data provide fresh insights into the evolutionary and infection dynamics of the virus population within the host, revealing that HIV-1 can continue to replicate and refill the viral reservoir despite potent antiretroviral therapy. PMID:26814962

  1. Migratory Passerine Birds as Reservoirs of Lyme Borreliosis in Europe

    PubMed Central

    Comstedt, Pär; Bergström, Sven; Olsen, Björn; Garpmo, Ulf; Marjavaara, Lisette; Mejlon, Hans; Barbour, Alan G.

    2006-01-01

    To define the role of birds as reservoirs and disseminators of Borrelia spirochetes, we characterized tick infestation and reservoir competence of migratory passerine birds in Sweden. A total of 1,120 immature Ixodes ricinus ticks were removed from 13,260 birds and assayed by quantitative polymerase chain reaction (PCR) for Borrelia, followed by DNA sequencing for species and genotype identification. Distributions of ticks on birds were aggregated, presumably because of varying encounters with ticks along migratory routes. Lyme borreliosis spirochetes were detected in 160 (14%) ticks. Borrelia garinii was the most common species in PCR-positive samples and included genotypes associated with human infections. Infestation prevalence with infected ticks was 5 times greater among ground-foraging birds than other bird species, but the 2 groups were equally competent in transmitting Borrelia. Migratory passerine birds host epidemiologically important vector ticks and Borrelia species and vary in effectiveness as reservoirs on the basis of their feeding behavior. PMID:16836825

  2. All-optical reservoir computing.

    PubMed

    Duport, François; Schneider, Bendix; Smerieri, Anteo; Haelterman, Marc; Massar, Serge

    2012-09-24

    Reservoir Computing is a novel computing paradigm that uses a nonlinear recurrent dynamical system to carry out information processing. Recent electronic and optoelectronic Reservoir Computers based on an architecture with a single nonlinear node and a delay loop have shown performance on standardized tasks comparable to state-of-the-art digital implementations. Here we report an all-optical implementation of a Reservoir Computer, made of off-the-shelf components for optical telecommunications. It uses the saturation of a semiconductor optical amplifier as nonlinearity. The present work shows that, within the Reservoir Computing paradigm, all-optical computing with state-of-the-art performance is possible.

  3. Poxviruses and the Evolution of Host Range and Virulence

    PubMed Central

    Haller, Sherry L.; Peng, Chen; McFadden, Grant; Rothenburg, Stefan

    2013-01-01

    Poxviruses as a group can infect a large number of animals. However, at the level of individual viruses, even closely related poxviruses display highly diverse host ranges and virulence. For example, variola virus, the causative agent of smallpox, is human-specific and highly virulent only to humans, whereas related cowpox viruses naturally infect a broad spectrum of animals and only cause relatively mild disease in humans. The successful replication of poxviruses depends on their effective manipulation of the host antiviral responses, at the cellular-, tissue- and species-specific levels, which constitutes a molecular basis for differences in poxvirus host range and virulence. A number of poxvirus genes have been identified that possess host range function in experimental settings, and many of these host range genes target specific antiviral host pathways. Herein, we review the biology of poxviruses with a focus on host range, zoonotic infections, virulence, genomics and host range genes as well as the current knowledge about the function of poxvirus host range factors and how their interaction with the host innate immune system contributes to poxvirus host range and virulence. We further discuss the evolution of host range and virulence in poxviruses as well as host switches and potential poxvirus threats for human and animal health. PMID:24161410

  4. Farm Animals

    MedlinePlus

    ... Pets Pets Birds Cats Dogs Farm Animals Backyard Poultry Ferrets Fish Horses Reptiles and Amphibians Turtles Kept ... including cattle; sheep; pigs; goats; llamas; alpacas; and poultry only happens at petting zoos or on farm ...

  5. Suzaku Animation

    NASA Video Gallery

    This animation depicts the Suzaku spacecraft. Suzaku (originally known as Astro-E2) was launched July 10, 2005, and maintains a low-Earth orbit while it observes X-rays from the universe. The satel...

  6. Pulsar Animation

    NASA Video Gallery

    Pulsars are thought to emit relatively narrow radio beams, shown as green in this animation. If these beams don't sweep toward Earth, astronomers cannot detect the radio signals. Pulsar gamma-ray e...

  7. Wild Animals.

    ERIC Educational Resources Information Center

    Web Feet K-8, 2000

    2000-01-01

    This annotated subject guide to Web sites and other resources focuses on wild animals. Includes Web sites, CD-ROMs and software, videos, books, audios, magazines, and professional resources, as well as a class activity. (LRW)

  8. Wildlife disease reservoirs: the epidemiology of Mycobacterium bovis infection in the European badger (Meles meles) and other British mammals.

    PubMed

    Delahay, R J; Cheeseman, C L; Clifton-Hadley, R S

    2001-01-01

    Mycobacterium bovis infection has been confirmed in a wide range of mammals hosts throughout the world. The European badger (Meles meles) and the brushtail possum (Trichosurus vulpecula) are implicated as significant sources of infection for domestic cattle in the UK and New Zealand respectively. The risk of transmission of infection between a wildlife population and domestic animals will be determined by both the epidemiology of the disease and the ecology of the host. In the UK, surveys by the UK Ministry of Agriculture, Fisheries and Food (MAFF) have identified M. bovis infection in deer (Cervus sp., Capreolus sp., Dama sp.), red fox (Vulpes vulpes), mink (Mustela vison), feral ferret (Mustela furo), mole (Talpa europaea), brown rat (Rattus norvegicus) and feral cat (Felis catus). However, the potential contribution to cattle herd breakdowns, of reservoirs of M. bovis infection in mammals other than the badger is poorly understood and is the subject of current research. In contrast, M. bovis infection in the badger has been the subject of a long term ecological and epidemiological study at Woodchester Park in South-West England, where the prevalence and distribution of infection in a wild population has been intensively monitored. The pattern of infection in the population and potential risks to cattle, are profoundly influenced by badger social organization and behaviour. The pattern of land use and cattle farming practices in the UK brings badgers into close contact with domestic animals and provides conditions that may enhance the likelihood of disease transfer.

  9. Toxocara spp. infections in paratenic hosts.

    PubMed

    Strube, Christina; Heuer, Lea; Janecek, Elisabeth

    2013-04-15

    The zoonotic roundworms Toxocara canis and T. cati are not only present worldwide in their definitive hosts; they also frequently occur in other animal species, including humans. In those so-called paratenic hosts, the larvae do not develop into the adult stage, but rather migrate throughout the somatic tissue and persist as infectious L3 stage for extensive periods. Those arrested larvae may lead to severe inflammatory reactions and consequently to a wide range of pathological and clinical manifestations. However, the infected paratenic hosts also constitute a potential source of infection for the definitive hosts or humans who may also function as paratenic hosts. In the present review, current knowledge of larval migration in a variety of possible paratenic hosts is summarized including variations of migration routes and susceptibilities. Furthermore, information about the clinical and pathological changes for the presented species and possible consequences of the somatic migration of larvae, i.e. the resulting tissue damage as well as adverse host reactions to arrested larvae are reviewed. There are still many questions unanswered regarding larval behaviour in hosts other than their definitive host. Therefore, it is of great importance to continue further elaboration on the biology of Toxocara spp. to prevent further spreading of larvae in both the paratenic and the definitive host.

  10. Companion animals symposium: humanized animal models of the microbiome.

    PubMed

    Gootenberg, D B; Turnbaugh, P J

    2011-05-01

    Humans and other mammals are colonized by trillions of microorganisms, most of which reside in the gastrointestinal tract, that provide key metabolic capabilities, such as the biosynthesis of vitamins and AA, the degradation of dietary plant polysaccharides, and the metabolism of orally administered therapeutics. Although much progress has been made by studying the human microbiome directly, comparing the human microbiome with that of other animals, and constructing in vitro models of the human gut, there remains a need to develop in vivo models where host, microbial, and environmental parameters can be manipulated. Here, we discuss some of the initial results from a promising method that enables the direct manipulation of microbial community structure, environmental exposures, host genotype, and other factors: the colonization of germ-free animals with complex microbial communities, including those from humans or other animal donors. Analyses of these resulting "humanized" gut microbiomes have begun to reveal 1) that key microbial activities can be transferred from the donor to the recipient animal (e.g., microbial reduction of cholesterol and production of equol), 2) that dietary shifts can affect the composition, gene abundance, and gene expression of the gut microbiome, 3) the succession of the microbial community in infants and ex-germ-free adult animals, and 4) the biogeography of these microbes across the length of gastrointestinal tract. Continued studies of humanized and other intentionally colonized animal models stand to provide new insight into not only the human microbiome, but also the microbiomes of our animal companions.

  11. Animal Bioacoustics

    NASA Astrophysics Data System (ADS)

    Fletcher, Neville H.

    Animals rely upon their acoustic and vibrational senses and abilities to detect the presence of both predators and prey and to communicate with members of the same species. This chapter surveys the physical bases of these abilities and their evolutionary optimization in insects, birds, and other land animals, and in a variety of aquatic animals other than cetaceans, which are treated in Chap. 20. While there are many individual variations, and some animals devote an immense fraction of their time and energy to acoustic communication, there are also many common features in their sound production and in the detection of sounds and vibrations. Excellent treatments of these matters from a biological viewpoint are given in several notable books [19.1,2] and collections of papers [19.3,4,5,6,7,8], together with other more specialized books to be mentioned in the following sections, but treatments from an acoustical viewpoint [19.9] are rare. The main difference between these two approaches is that biological books tend to concentrate on anatomical and physiological details and on behavioral outcomes, while acoustical books use simplified anatomical models and quantitative analysis to model vocalization frequency scaling in animals hearing sound production animal animal biological biological bioacoustics whole-system behavior. This latter is the approach to be adopted here.

  12. Further investigation of exposure to Lawsonia intracellularis in wild and feral animals captured on horse properties with equine proliferative enteropathy.

    PubMed

    Pusterla, Nicola; Mapes, Samantha; Gebhart, Connie

    2012-11-01

    This study investigated the exposure to Lawsonia intracellularis in wild birds, mice, rabbits, raccoons, coyotes and squirrels, and feral cats and pigs on 10 farms with confirmed equine proliferative enteropathy (EPE). Serum samples from all resident foals (417 samples) as well as fecal (461) and serum (106) samples from wild and feral animals were collected for serological and molecular detection of L. intracellularis following the diagnosis of EPE in index cases. A total of three cats from two farms, three mice from two farms and eight cottontail rabbits from one farm had evidence of prior exposure to L. intracellularis. These animals may be an indicator of environmental exposure or may be actively involved in the transmission of L. intracellularis to foals by acting as a potential reservoir/amplifier host.

  13. Ecology of antimicrobial resistance: humans, animals, food and environment.

    PubMed

    González-Zorn, Bruno; Escudero, José A

    2012-09-01

    Antimicrobial resistance is a major health problem. After decades of research, numerous difficulties in tackling resistance have emerged, from the paucity of new antimicrobials to the inefficient contingency plans to reduce the use of antimicrobials; consequently, resistance to these drugs is out of control. Today we know that bacteria from the environment are often at the very origin of the acquired resistance determinants found in hospitals worldwide. Here we define the genetic components that flow from the environment to pathogenic bacteria and thereby confer a quantum increase in resistance levels, as resistance units (RU). Environmental bacteria as well as microbiomes from humans, animals, and food represent an infinite reservoir of RU, which are based on genes that have had, or not, a resistance function in their original bacterial hosts. This brief review presents our current knowledge of antimicrobial resistance and its consequences, with special focus on the importance of an ecologic perspective of antimicrobial resistance. This discipline encompasses the study of the relationships of entities and events in the framework of curing and preventing disease, a definition that takes into account both microbial ecology and antimicrobial resistance. Understanding the flux of RU throughout the diverse ecosystems is crucial to assess, prevent and eventually predict emerging scaffolds before they colonize health institutions. Collaborative horizontal research scenarios should be envisaged and involve all actors working with humans, animals, food and the environment.

  14. Geological control on the reservoir characteristics of Olkaria West Geothermal Field, Kenya

    SciTech Connect

    Omenda, Peter A.

    1994-01-20

    The reservoir of the West Olkaria Geothermal Field is hosted within tuffs and the reservoir fluid is characterized by higher concentrations of reservoir CO{sub 2} (10,000-100,000 mg/kg) but lower chloride concentrations of about 200 mg/kg than the East and North East Fields. The West Field is in the outflow and main recharge area of the Olkaria geothermal system. Permeability is generally low in the West Field and its distribution is strongly controlled by the structures. Fault zones show higher permeability with wells drilled within the structures havin larger total mass outputs. However, N-S and NW-SE faults are mainly channels for cold water downflow into the reservoir. Well feeder zones occur mostly at lava-tuff contacts; within fractured lava flows and at the contacts of intrusives and host rocks.

  15. Coxiella burnetii Infects Primary Bovine Macrophages and Limits Their Host Cell Response

    PubMed Central

    Sobotta, Katharina; Hillarius, Kirstin; Mager, Marvin; Kerner, Katharina; Heydel, Carsten

    2016-01-01

    Although domestic ruminants have long been recognized as the main source of human Q fever, little is known about the lifestyle that the obligate intracellular Gram-negative bacterium Coxiella burnetii adopts in its animal host. Because macrophages are considered natural target cells of the pathogen, we established primary bovine monocyte-derived macrophages (MDM) as an in vitro infection model to study reservoir host-pathogen interactions at the cellular level. In addition, bovine alveolar macrophages were included to take cell type peculiarities at a host entry site into account. Cell cultures were inoculated with the virulent strain Nine Mile I (NMI; phase I) or the avirulent strain Nine Mile II (NMII; phase II). Macrophages from both sources internalized NMI and NMII. MDM were particularly permissive for NMI internalization, but NMI and NMII replicated with similar kinetics in these cells. MDM responded to inoculation with a general upregulation of Th1-related cytokines such as interleukin-1β (IL-1β), IL-12, and tumor necrosis factor alpha (TNF-α) early on (3 h postinfection). However, inflammatory responses rapidly declined when C. burnetii replication started. C. burnetii infection inhibited translation and release of IL-1β and vastly failed to stimulate increased expression of activation markers, such as CD40, CD80, CD86, and major histocompatibility complex (MHC) molecules. Such capability of limiting proinflammatory responses may help Coxiella to protect itself from clearance by the host immune system. The findings provide the first detailed insight into C. burnetii-macrophage interactions in ruminants and may serve as a basis for assessing the virulence and the host adaptation of C. burnetii strains. PMID:27021246

  16. Coxiella burnetii Infects Primary Bovine Macrophages and Limits Their Host Cell Response.

    PubMed

    Sobotta, Katharina; Hillarius, Kirstin; Mager, Marvin; Kerner, Katharina; Heydel, Carsten; Menge, Christian

    2016-06-01

    Although domestic ruminants have long been recognized as the main source of human Q fever, little is known about the lifestyle that the obligate intracellular Gram-negative bacterium Coxiella burnetii adopts in its animal host. Because macrophages are considered natural target cells of the pathogen, we established primary bovine monocyte-derived macrophages (MDM) as an in vitro infection model to study reservoir host-pathogen interactions at the cellular level. In addition, bovine alveolar macrophages were included to take cell type peculiarities at a host entry site into account. Cell cultures were inoculated with the virulent strain Nine Mile I (NMI; phase I) or the avirulent strain Nine Mile II (NMII; phase II). Macrophages from both sources internalized NMI and NMII. MDM were particularly permissive for NMI internalization, but NMI and NMII replicated with similar kinetics in these cells. MDM responded to inoculation with a general upregulation of Th1-related cytokines such as interleukin-1β (IL-1β), IL-12, and tumor necrosis factor alpha (TNF-α) early on (3 h postinfection). However, inflammatory responses rapidly declined when C. burnetii replication started. C. burnetii infection inhibited translation and release of IL-1β and vastly failed to stimulate increased expression of activation markers, such as CD40, CD80, CD86, and major histocompatibility complex (MHC) molecules. Such capability of limiting proinflammatory responses may help Coxiella to protect itself from clearance by the host immune system. The findings provide the first detailed insight into C. burnetii-macrophage interactions in ruminants and may serve as a basis for assessing the virulence and the host adaptation of C. burnetii strains.

  17. Pseudoneoplasms in ectothermic animals.

    PubMed

    Harshbarger, J C

    1984-05-01

    Gross and cytologic similarities between certain non-neoplastic conditions and neoplasms in lower animals including fish, amphibians, and reptiles have invited misinterpretations and contested interpretations. Major categories of pseudo-neoplasms, illustrated by specific examples from material accessioned into the Registry of Tumors in Lower Animals, include infections by foreign organisms which resemble host cells (algal protothecosis and amebic pseudotumors); unusual normal conditions [giant islets of endocrine pancreas (Brockmann bodies) in liver, atypical sites of hematopoietic tissue]; nonparasitic hyperplasia (goiter, ectopic thyroid, erythroblastic proliferation suggestive of pernicious anemia, adenofibrosis); parasite-induced hyperplasia (trematode-induced fibrosis, ciliate-induced monocytic leukocytosis, trematode-induced melanosis, glochidiosis); dysmorphogenesis (teratoid anomalies); virus-induced hypertrophy (lymphocystis); and reactive lesions (metaplasia, regeneration, inflammation).

  18. Coupling Vector-host Dynamics with Weather Geography and Mitigation Measures to Model Rift Valley Fever in Africa

    PubMed Central

    McMahon, B.H.; Manore, C.A.; Hyman, J.M.; LaBute, M.X.; Fair, J.M.

    2015-01-01

    We present and characterize a multi-host epidemic model of Rift Valley fever (RVF) virus in East Africa with geographic spread on a network, rule-based mitigation measures, and mosquito infection and population dynamics. Susceptible populations are depleted by disease and vaccination and are replenished with the birth of new animals. We observe that the severity of the epidemics is strongly correlated with the duration of the rainy season and that even severe epidemics are abruptly terminated when the rain stops. Because naturally acquired herd immunity is established, total mortality across 25 years is relatively insensitive to many mitigation approaches. Strong reductions in cattle mortality are expected, however, with sufficient reduction in population densities of either vectors or susceptible (ie. unvaccinated) hosts. A better understanding of RVF epidemiology would result from serology surveys to quantify the importance of herd immunity in epidemic control, and sequencing of virus from representative animals to quantify the realative importance of transportation and local reservoirs in nucleating yearly epidemics. Our results suggest that an effective multi-layered mitigation strategy would include vector control, movement control, and vaccination of young animals yearly, even in the absence of expected rainfall. PMID:25892858

  19. Reservoir Modeling for Production Management

    SciTech Connect

    Brown, Donald W.

    1989-03-21

    For both petroleum and geothermal resources, many of the reservoirs are fracture dominated--rather than matrix-permeability controlled. For such reservoirs, a knowledge of the pressure-dependent permeability of the interconnected system of natural joints (i.e., pre-existing fractures) is critical to the efficient exploitation of the resource through proper pressure management. Our experience and that reported by others indicates that a reduction in the reservoir pressure sometimes leads to an overall reduction in production rate due to the ''pinching off'' of the joint network, rather than the anticipated increase in production rate. This effect occurs not just in the vicinity of the wellbore, where proppants are sometimes employed, but throughout much of the reservoir region. This follows from the fact that under certain circumstances, the decline in fracture permeability (or conductivity) with decreasing reservoir pressure exceeds the far-field reservoir ''drainage'' flow rate increase due to the increased pressure gradient. Further, a knowledge of the pressure-dependent joint permeability could aid in designing more appropriate secondary recovery strategies in petroleum reservoirs or reinjection procedures for geothermal reservoirs.

  20. HEC Activities in Reservoir Analysis.

    DTIC Science & Technology

    1980-06-01

    June 1979. Now, HEC-5, "Simulation of Flood Con- trol and Conservation Systems," (9) is our primary reservoir simulation program. Since its June release...are being incorporated into the reservoir simulation model HEC-5. The objective is to provide a computer program and methodology for total water

  1. Tertiary carbonate reservoirs in Indonesia

    SciTech Connect

    Nayoan, G.A.S.; Arpandi; Siregar, M.

    1981-01-01

    Hydrocarbon production from Tertiary carbonate reservoirs accounted for ca. 10% of daily Indonesian production at the beginning of 1978. Environmentally, the reservoirs appear as parts of reef complexes and high-energy carbonate deposits within basinal areas situated mainly in the back arc of the archipelago. Good porosities of the reservoirs are represented by vugular/moldic and intergranular porosity types. The reservoirs are capable of producing prolific amounts of hydrocarbons: production tests in Salawati-Irian Jaya reaches maximum values of 32,000 bpd, and in Arun-North Sumatra tests recorded 200 MMCF gas/day. Significant hydrocarbon accumulations are related to good reservoir rocks in carbonates deposited as patch reefs, pinnacle reefs, and platform complexes. Exploration efforts expand continuously within carbonate formations which are extensive horizontally as well as vertically in the Tertiary stratigraphic column.

  2. Stochastic thermodynamics with information reservoirs

    NASA Astrophysics Data System (ADS)

    Barato, Andre C.; Seifert, Udo

    2014-10-01

    We generalize stochastic thermodynamics to include information reservoirs. Such information reservoirs, which can be modeled as a sequence of bits, modify the second law. For example, work extraction from a system in contact with a single heat bath becomes possible if the system also interacts with an information reservoir. We obtain an inequality, and the corresponding fluctuation theorem, generalizing the standard entropy production of stochastic thermodynamics. From this inequality we can derive an information processing entropy production, which gives the second law in the presence of information reservoirs. We also develop a systematic linear response theory for information processing machines. For a unicyclic machine powered by an information reservoir, the efficiency at maximum power can deviate from the standard value of 1 /2 . For the case where energy is consumed to erase the tape, the efficiency at maximum erasure rate is found to be 1 /2 .

  3. FRACTURED PETROLEUM RESERVOIRS

    SciTech Connect

    Abbas Firoozabadi

    1999-06-11

    The four chapters that are described in this report cover a variety of subjects that not only give insight into the understanding of multiphase flow in fractured porous media, but they provide also major contribution towards the understanding of flow processes with in-situ phase formation. In the following, a summary of all the chapters will be provided. Chapter I addresses issues related to water injection in water-wet fractured porous media. There are two parts in this chapter. Part I covers extensive set of measurements for water injection in water-wet fractured porous media. Both single matrix block and multiple matrix blocks tests are covered. There are two major findings from these experiments: (1) co-current imbibition can be more efficient than counter-current imbibition due to lower residual oil saturation and higher oil mobility, and (2) tight fractured porous media can be more efficient than a permeable porous media when subjected to water injection. These findings are directly related to the type of tests one can perform in the laboratory and to decide on the fate of water injection in fractured reservoirs. Part II of Chapter I presents modeling of water injection in water-wet fractured media by modifying the Buckley-Leverett Theory. A major element of the new model is the multiplication of the transfer flux by the fractured saturation with a power of 1/2. This simple model can account for both co-current and counter-current imbibition and computationally it is very efficient. It can be orders of magnitude faster than a conventional dual-porosity model. Part II also presents the results of water injection tests in very tight rocks of some 0.01 md permeability. Oil recovery from water imbibition tests from such at tight rock can be as high as 25 percent. Chapter II discusses solution gas-drive for cold production from heavy-oil reservoirs. The impetus for this work is the study of new gas phase formation from in-situ process which can be significantly

  4. Meandering stream reservoirs

    SciTech Connect

    Richardson, J.G.; Sangree, J.B.; Sneider, R.M.

    1987-12-01

    Braided stream deposits, described in a previous article in this series, and meandering stream deposits commonly are excellent reservoirs. Meandering high-sinuousity channels are found on flat alluvial plains with slopes less than 1 1/2/sup 0/ (0.026 rad). These rivers have wide ranges of discharges from low-water flow to flood stage. Two main processes are responsible for development of sand bodies. These are point-bar deposits left by channel migration, and oxbow-lake deposits left in loops of the river course abandoned when the stream cuts a new course during flooding. Extremely high floods spill over the banks and deposit sheets of very fine sand, silt, and clay onto the flood plain.

  5. Bats as Viral Reservoirs.

    PubMed

    Hayman, David T S

    2016-09-29

    Bats are hosts of a range of viruses, including ebolaviruses, and many important human viral infections, such as measles and mumps, may have their ancestry traced back to bats. Here, I review viruses of all viral families detected in global bat populations. The viral diversity in bats is substantial, and viruses with all known types of genomic structures and replication strategies have been discovered in bats. However, the discovery of viruses is not geographically even, with some apparently undersampled regions, such as South America. Furthermore, some bat families, including those with global or wide distributions such as Emballonuridae and Miniopteridae, are underrepresented on viral databases. Future studies, including those that address these sampling gaps along with those that develop our understanding of viral-host relationships, are highlighted.

  6. Biosafety considerations for in vivo work with risk group 3 pathogens in large animals and wildlife in North America.

    PubMed

    Olsen, S C

    2013-06-01

    Regulations in the United States require animal biosafety level 3 (ABSL-3) or biosafety level 3 agriculture (BSL-3-Ag) containment for many endemic zoonotic pathogens and etiologic agents of foreign animal diseases. In an effort to protect public health, billions of dollars were invested in regulatory programs over many years to reduce the prevalence of zoonotic pathogens such as Brucella and Mycobacterium bovis in domestic livestock. In addition to research needs in domestic livestock hosts, the establishment of brucellosis and tuberculosis in wildlife in the United States has created a need for research studies addressing these zoonotic diseases. As guidelines in the Biosafety in Microbiological and Biomedical Laboratories (BMBL, 2009) for BSL-3 and BSL-3-Ag facilities are primarily directed toward laboratory or vivarium facilities, additional issues should be considered in designing large animal containment facilities for domestic livestock and/or wildlife. Flight distance, herd orientation, social needs, aggressiveness, and predictability are all factors we considered on a species by species basis for designing our containment facilities and for work practices with large ruminants. Although safety risk cannot be completely eliminated when working with large animals, studies in natural hosts are critical for advancing vaccine and diagnostic development, and providing basic knowledge of disease pathogenesis in natural hosts. Data gathered in these types of studies are vital for state and national regulatory personnel in their efforts to design strategies to control or eradicate diseases such as brucellosis and tuberculosis in their natural hosts, whether it is domestic livestock or wildlife. It is likely that failure to address the prevalence of disease in wildlife reservoirs will lead to re-emergence in domestic livestock. The overall benefit of these studies is to protect public health, provide economic benefits to producers, and protect the economic investment

  7. Comprehensive Serology Based on a Peptide ELISA to Assess the Prevalence of Closely Related Equine Herpesviruses in Zoo and Wild Animals.

    PubMed

    Abdelgawad, Azza; Hermes, Robert; Damiani, Armando; Lamglait, Benjamin; Czirják, Gábor Á; East, Marion; Aschenborn, Ortwin; Wenker, Christian; Kasem, Samy; Osterrieder, Nikolaus; Greenwood, Alex D

    2015-01-01

    Equine herpesvirus type 1 (EHV-1) causes respiratory disorders and abortion in equids while EHV-1 regularly causes equine herpesvirus myeloencephalopathy (EHM), a stroke-like syndrome following endothelial cell infection in horses. Both EHV-1 and EHV-9 infections of non-definitive hosts often result in neuronal infection and high case fatality rates. Hence, EHV-1 and EHV-9 are somewhat unusual herpesviruses and lack strict host specificity, and the true extent of their host ranges have remained unclear. In order to determine the seroprevalence of EHV-1 and EHV-9, a sensitive and specific peptide-based ELISA was developed and applied to 428 sera from captive and wild animals representing 30 species in 12 families and five orders. Members of the Equidae, Rhinocerotidae and Bovidae were serologically positive for EHV-1 and EHV-9. The prevalence of EHV-1 in the sampled wild zebra populations was significantly higher than in zoos suggesting captivity may reduce exposure to EHV-1. Furthermore, the seroprevalence for EHV-1 was significantly higher than for EHV-9 in zebras. In contrast, EHV-9 antibody prevalence was high in captive and wild African rhinoceros species suggesting that they may serve as a reservoir or natural host for EHV-9. Thus, EHV-1 and EHV-9 have a broad host range favoring African herbivores and may have acquired novel natural hosts in ecosystems where wild equids are common and are in close contact with other perissodactyls.

  8. Comprehensive Serology Based on a Peptide ELISA to Assess the Prevalence of Closely Related Equine Herpesviruses in Zoo and Wild Animals

    PubMed Central

    Abdelgawad, Azza; Hermes, Robert; Damiani, Armando; Lamglait, Benjamin; Czirják, Gábor Á.; East, Marion; Aschenborn, Ortwin; Wenker, Christian; Kasem, Samy; Osterrieder, Nikolaus; Greenwood, Alex D.

    2015-01-01

    Equine herpesvirus type 1 (EHV-1) causes respiratory disorders and abortion in equids while EHV-1 regularly causes equine herpesvirus myeloencephalopathy (EHM), a stroke-like syndrome following endothelial cell infection in horses. Both EHV-1 and EHV-9 infections of non-definitive hosts often result in neuronal infection and high case fatality rates. Hence, EHV-1 and EHV-9 are somewhat unusual herpesviruses and lack strict host specificity, and the true extent of their host ranges have remained unclear. In order to determine the seroprevalence of EHV-1 and EHV-9, a sensitive and specific peptide-based ELISA was developed and applied to 428 sera from captive and wild animals representing 30 species in 12 families and five orders. Members of the Equidae, Rhinocerotidae and Bovidae were serologically positive for EHV-1 and EHV-9. The prevalence of EHV-1 in the sampled wild zebra populations was significantly higher than in zoos suggesting captivity may reduce exposure to EHV-1. Furthermore, the seroprevalence for EHV-1 was significantly higher than for EHV-9 in zebras. In contrast, EHV-9 antibody prevalence was high in captive and wild African rhinoceros species suggesting that they may serve as a reservoir or natural host for EHV-9. Thus, EHV-1 and EHV-9 have a broad host range favoring African herbivores and may have acquired novel natural hosts in ecosystems where wild equids are common and are in close contact with other perissodactyls. PMID:26378452

  9. Water resources review: Ocoee reservoirs, 1990

    SciTech Connect

    Cox, J.P.

    1990-08-01

    Tennessee Valley Authority (TVA) is preparing a series of reports to make technical information on individual TVA reservoirs readily accessible. These reports provide a summary of reservoir purpose and operation; physical characteristics of the reservoir and watershed; water quality conditions; aquatic biological conditions; and designated, actual and potential uses of the reservoir and impairments of those use. This reservoir status report addressed the three Ocoee Reservoirs in Polk County, Tennessee.

  10. Collapsible sheath fluid reservoirs for flow cytometers

    DOEpatents

    Mark, Graham A.

    2000-01-01

    The present invention is a container in the form of a single housing for holding fluid, including a first collapsible reservoir having a first valve. The first reservoir initially contains a volume of fluid. The container also includes a second reservoir, initially empty (or substantially empty), expandable to a second volume. The second reservoir has a second valve. As the volume of said first reservoir decreases, the volume of the second reservoir proportionally increases.

  11. Animal Bioacoustics

    NASA Astrophysics Data System (ADS)

    Fletcher, Neville

    Animals rely upon their acoustic and vibrational senses and abilities to detect the presence of both predators and prey and to communicate with members of the same species. This chapter surveys the physical bases of these abilities and their evolutionary optimization in insects, birds, and other land animals, and in a variety of aquatic animals other than cetaceans, which are treated in Chap. 20. While there are many individual variations, and some animals devote an immense fraction of their time and energy to acoustic communication, there are also many common features in their sound production and in the detection of sounds and vibrations. Excellent treatments of these matters from a biological viewpoint are given in several notable books [19.1,2] and collections of papers [19.3,4,5,6,7,8], together with other more specialized books to be mentioned in the following sections, but treatments from an acoustical viewpoint [19.9] are rare. The main difference between these two approaches is that biological books tend to concentrate on anatomical and physiological details and on behavioral outcomes, while acoustical books use simplified anatomical models and quantitative analysis to model whole-system behavior. This latter is the approach to be adopted here.

  12. Animal Science.

    ERIC Educational Resources Information Center

    VanCleave, Janice

    2001-01-01

    Presents a set of hands-on, outdoor science experiments designed to teach elementary school students about animal adaptation. The experiments focus on: how color camouflage affects an insect population; how spiderlings find a home; and how chameleons camouflage themselves by changing color. (SM)

  13. Transgenic Animals.

    ERIC Educational Resources Information Center

    Jaenisch, Rudolf

    1988-01-01

    Describes three methods and their advantages and disadvantages for introducing genes into animals. Discusses the predictability and tissue-specificity of the injected genes. Outlines the applications of transgenic technology for studying gene expression, the early stages of mammalian development, mutations, and the molecular nature of chromosomes.…

  14. Analysis of real-time reservoir monitoring : reservoirs, strategies, & modeling.

    SciTech Connect

    Mani, Seethambal S.; van Bloemen Waanders, Bart Gustaaf; Cooper, Scott Patrick; Jakaboski, Blake Elaine; Normann, Randy Allen; Jennings, Jim; Gilbert, Bob; Lake, Larry W.; Weiss, Chester Joseph; Lorenz, John Clay; Elbring, Gregory Jay; Wheeler, Mary Fanett; Thomas, Sunil G.; Rightley, Michael J.; Rodriguez, Adolfo; Klie, Hector; Banchs, Rafael; Nunez, Emilio J.; Jablonowski, Chris

    2006-11-01

    The project objective was to detail better ways to assess and exploit intelligent oil and gas field information through improved modeling, sensor technology, and process control to increase ultimate recovery of domestic hydrocarbons. To meet this objective we investigated the use of permanent downhole sensors systems (Smart Wells) whose data is fed real-time into computational reservoir models that are integrated with optimized production control systems. The project utilized a three-pronged approach (1) a value of information analysis to address the economic advantages, (2) reservoir simulation modeling and control optimization to prove the capability, and (3) evaluation of new generation sensor packaging to survive the borehole environment for long periods of time. The Value of Information (VOI) decision tree method was developed and used to assess the economic advantage of using the proposed technology; the VOI demonstrated the increased subsurface resolution through additional sensor data. Our findings show that the VOI studies are a practical means of ascertaining the value associated with a technology, in this case application of sensors to production. The procedure acknowledges the uncertainty in predictions but nevertheless assigns monetary value to the predictions. The best aspect of the procedure is that it builds consensus within interdisciplinary teams The reservoir simulation and modeling aspect of the project was developed to show the capability of exploiting sensor information both for reservoir characterization and to optimize control of the production system. Our findings indicate history matching is improved as more information is added to the objective function, clearly indicating that sensor information can help in reducing the uncertainty associated with reservoir characterization. Additional findings and approaches used are described in detail within the report. The next generation sensors aspect of the project evaluated sensors and packaging

  15. Data requirements and acquisition for reservoir characterization

    SciTech Connect

    Jackson, S.; Chang, Ming Ming; Tham, Min.

    1993-03-01

    This report outlines the types of data, data sources and measurement tools required for effective reservoir characterization, the data required for specific enhanced oil recovery (EOR) processes, and a discussion on the determination of the optimum data density for reservoir characterization and reservoir modeling. The two basic sources of data for reservoir characterization are data from the specific reservoir and data from analog reservoirs, outcrops, and modern environments. Reservoir data can be divided into three broad categories: (1) rock properties (the container) and (2) fluid properties (the contents) and (3)interaction between reservoir rock and fluid. Both static and dynamic measurements are required.

  16. Emergence of zoonotic arboviruses by animal trade and migration.

    PubMed

    Pfeffer, Martin; Dobler, Gerhard

    2010-04-08

    Arboviruses are transmitted in nature exclusively or to a major extend by arthropods. They belong to the most important viruses invading new areas in the world and their occurrence is strongly influenced by climatic changes due to the life cycle of the transmitting vectors. Several arboviruses have emerged in new regions of the world during the last years, like West Nile virus (WNV) in the Americas, Usutu virus (USUV) in Central Europe, or Rift Valley fever virus (RVFV) in the Arabian Peninsula. In most instances the ways of introduction of arboviruses into new regions are not known. Infections acquired during stays in the tropics and subtropics are diagnosed with increasing frequency in travellers returning from tropical countries, but interestingly no attention is paid on accompanying pet animals or the hematophagous ectoparasites that may still be attached to them. Here we outline the known ecology of the mosquito-borne equine encephalitis viruses (WEEV, EEEV, and VEEV), WNV, USUV, RVFV, and Japanese Encephalitis virus, as well as Tick-Borne Encephalitis virus and its North American counterpart Powassan virus, and will discuss the most likely mode that these viruses could expand their respective geographical range. All these viruses have a different epidemiology as different vector species, reservoir hosts and virus types have adapted to promiscuous and robust or rather very fine-balanced transmission cycles. Consequently, these viruses will behave differently with regard to the requirements needed to establish new endemic foci outside their original geographical ranges. Hence, emphasis is given on animal trade and suitable ecologic conditions, including competent vectors and vertebrate hosts.

  17. Antivirals against animal viruses.

    PubMed

    Villa, T G; Feijoo-Siota, L; Rama, J L R; Ageitos, J M

    2016-09-30

    Antivirals are compounds used since the 1960s that can interfere with viral development. Some of these antivirals can be isolated from a variety of sources, such as animals, plants, bacteria or fungi, while others must be obtained by chemical synthesis, either designed or random. Antivirals display a variety of mechanisms of action, and while some of them enhance the animal immune system, others block a specific enzyme or a particular step in the viral replication cycle. As viruses are mandatory intracellular parasites that use the host's cellular machinery to survive and multiply, it is essential that antivirals do not harm the host. In addition, viruses are continually developing new antiviral resistant strains, due to their high mutation rate, which makes it mandatory to continually search for, or develop, new antiviral compounds. This review describes natural and synthetic antivirals in chronological order, with an emphasis on natural compounds, even when their mechanisms of action are not completely understood, that could serve as the basis for future development of novel and/or complementary antiviral treatments.

  18. Identification of Bacterial Specialists in Hosts belonging to Aves, Mammalia, and Pisces

    EPA Science Inventory

    Only a portion of bacteria found in animal guts are able to establish specific associations within animal hosts. Taxa that have formed these specialized relationships may have played a prominent role in host evolution and may also contribute significantly to current host physiolo...

  19. Bartonella entry mechanisms into mammalian host cells.

    PubMed

    Eicher, Simone C; Dehio, Christoph

    2012-08-01

    The Gram-negative genus Bartonella comprises arthropod-borne pathogens that typically infect mammals in a host-specific manner. Bartonella bacilliformis and Bartonella quintana are human-specific pathogens, while several zoonotic bartonellae specific for diverse animal hosts infect humans as an incidental host. Clinical manifestations of Bartonella infections range from mild symptoms to life-threatening disease. Following transmission by blood-sucking arthropods or traumatic contact with infected animals, bartonellae display sequential tropisms towards endothelial and possibly other nucleated cells and erythrocytes, the latter in a host-specific manner. Attachment to the extracellular matrix (ECM) and to nucleated cells is mediated by surface-exposed bacterial adhesins, in particular trimeric autotransporter adhesins (TAAs). The subsequent engulfment of the pathogen into a vacuolar structure follows a unique series of events whereby the pathogen avoids the endolysosomal compartments. For Bartonella henselae and assumingly most other species, the infection process is aided at different steps by Bartonella effector proteins (Beps). They are injected into host cells through the type IV secretion system (T4SS) VirB/D4 and subvert host cellular functions to favour pathogen uptake. Bacterial binding to erythrocytes is mediated by Trw, another T4SS, in a strictly host-specific manner, followed by pathogen-forced uptake involving the IalB invasin and subsequent replication and persistence within a membrane-bound intra-erythrocytic compartment.

  20. Approaches to assessing host resistance.

    PubMed Central

    Bradley, S G; Morahan, P S

    1982-01-01

    There is increasing evidence that chronic, subclinical exposure to certain environmental pollutants may upset immune responsiveness and alter susceptibility of animals to infectious agents. Environmental chemicals or drugs may affect diverse aspects of the immune system, leading to immunosuppression, immunopotentiation, hypersensitivity or perturbed innate host resistance. A variety of infectious models is available that involves relatively well defined target organs and host defense mechanisms; for example, infections with encephalomyocarditis virus, Herpesvirus simplex, Listeria monocytogenes, Streptococcus pneumoniae, Escherichia coli or Plasmodium berghei. Important variables in infectious models used to assess immunotoxicity include species and strain of animal used, their age and sex, the route of exposure, and dose of the chemical. No one infectious model has yet emerged as a routine screening tool to detect and assess the subtle effects that may occur in immune responses when animals are exposed to doses of environmental pollutants that cause no adverse effect at a gross level. The selection of useful test systems is complicated because it is difficult to measure the effects of chronic, subclinical exposure to chemicals and sublethal challenges of microorganisms. PMID:6277617

  1. Mosquito Host Selection Varies Seasonally with Host Availability and Mosquito Density

    PubMed Central

    Thiemann, Tara C.; Wheeler, Sarah S.; Barker, Christopher M.; Reisen, William K.

    2011-01-01

    Host selection by vector mosquitoes is a critical component of virus proliferation, particularly for viruses such as West Nile (WNV) that are transmitted enzootically to a variety of avian hosts, and tangentially to dead-end hosts such as humans. Culex tarsalis is a principal vector of WNV in rural areas of western North America. Based on previous work, Cx. tarsalis utilizes a variety of avian and mammalian hosts and tends to feed more frequently on mammals in the late summer than during the rest of the year. To further explore this and other temporal changes in host selection, bloodfed females were collected at a rural farmstead and heron nesting site in Northern California from May 2008 through May 2009, and bloodmeal hosts identified using either a microsphere-based array or by sequencing of the mitochondrial cytochrome c oxidase I (COI) gene. Host composition during summer was dominated by four species of nesting Ardeidae. In addition, the site was populated with various passerine species as well as domestic farm animals and humans. When present, Cx. tarsalis fed predominantly (>80%) upon the ardeids, with Black-crowned Night-Herons, a highly competent WNV host, the most prevalent summer host. As the ardeids fledged and left the area and mosquito abundance increased in late summer, Cx. tarsalis feeding shifted to include more mammals, primarily cattle, and a high diversity of avian species. In the winter, Yellow-billed Magpies and House Sparrows were the predominant hosts, and Yellow-billed Magpies and American Robins were fed upon more frequently than expected given their relative abundance. These data demonstrated that host selection was likely based both on host availability and differences in utilization, that the shift of bloodfeeding to include more mammalian hosts was likely the result of both host availability and increased mosquito abundance, and that WNV-competent hosts were fed upon by Cx. tarsalis throughout the year. PMID:22206038

  2. Recent progress in henipavirus research: molecular biology, genetic diversity, animal models.

    PubMed

    Rockx, Barry; Winegar, Richard; Freiberg, Alexander N

    2012-08-01

    Nipah and Hendra virus are members of a newly identified genus of emerging paramyxoviruses, the henipaviruses. Both viruses have the ability to cause severe pulmonary infection and severe acute encephalitis. Following their discovery in the 1990s, outbreaks caused by these zoonotic paramyxoviruses have been associated with high public health and especially economic threat potential. Currently, only geographic groupings in Asia and Australia have been described for the henipaviruses. However, while few viral isolates are available and more detailed characterization is necessary, there has been recent evidence that divergent henipaviruses might be present on the African continent. This review endeavours to capture recent advances in the field of henipavirus research, with a focus on genome structure and replication mechanisms, reservoir hosts, genetic diversity, pathogenesis and animal models.

  3. [Dangerous animals].

    PubMed

    Hasle, Gunnar

    2002-06-30

    As travellers seek ever more exotic destinations they are more likely to encounter dangerous animals. Compared to risks such as AIDS, traffic accidents and malaria, the risk is not so great; many travellers are, however, concerned about this and those who give pre-travel vaccines and advice should know something about it. This article is mainly based on medical and zoological textbooks. Venomous stings and bites may be prevented by adequate clothing and by keeping safe distance to the animals. Listening to those who live in the area is of course important. Travellers should not carry antisera with them, but antisera should be available at local hospitals. It should be borne in mind that plant eaters cause just as many deaths as large predators. In some cases it is necessary to carry a sufficiently powerful firearm.

  4. Mark-recapture studies of host selection by Anopheles (Anopheles) vestitipennis.

    PubMed

    Ulloa, Armando; Arredondo-Jiménez, Juan I; Rodriguez, Mario H; Fernández-Salas, Ildefonso

    2002-03-01

    We present herein the results of a series of mark-recapture experiments with female Anopheles vestitipennis. Theses experiments used human and animal hosts to assess the degree of anthropophily of field-caught specimens, originally collected on either host, and of their offspring. Fidelity of mosquitoes to particular hosts was estimated by recapturing marked host-seeking mosquitoes returning for a 2nd blood meal. Results indicated that mosquitoes seeking animal hosts were more faithful (80.48%; 33 of 41) in returning to their original host than were those seeking human hosts (63%; 49 of 78).

  5. Interactions of Salmonella with animals and plants

    PubMed Central

    Wiedemann, Agnès; Virlogeux-Payant, Isabelle; Chaussé, Anne-Marie; Schikora, Adam; Velge, Philippe

    2015-01-01

    Salmonella enterica species are Gram-negative bacteria, which are responsible for a wide range of food- and water-borne diseases in both humans and animals, thereby posing a major threat to public health. Recently, there has been an increasing number of reports, linking Salmonella contaminated raw vegetables and fruits with food poisoning. Many studies have shown that an essential feature of the pathogenicity of Salmonella is its capacity to cross a number of barriers requiring invasion of a large variety of cells and that the extent of internalization may be influenced by numerous factors. However, it is poorly understood how Salmonella successfully infects hosts as diversified as animals or plants. The aim of this review is to describe the different stages required for Salmonella interaction with its hosts: (i) attachment to host surfaces; (ii) entry processes; (iii) multiplication; (iv) suppression of host defense mechanisms; and to point out similarities and differences between animal and plant infections. PMID:25653644

  6. Animal migration and infectious disease risk.

    PubMed

    Altizer, Sonia; Bartel, Rebecca; Han, Barbara A

    2011-01-21

    Animal migrations are often spectacular, and migratory species harbor zoonotic pathogens of importance to humans. Animal migrations are expected to enhance the global spread of pathogens and facilitate cross-species transmission. This does happen, but new research has also shown that migration allows hosts to escape from infected habitats, reduces disease levels when infected animals do not migrate successfully, and may lead to the evolution of less-virulent pathogens. Migratory demands can also reduce immune function, with consequences for host susceptibility and mortality. Studies of pathogen dynamics in migratory species and how these will respond to global change are urgently needed to predict future disease risks for wildlife and humans alike.

  7. Cascade Reservoirs Floodwater Resources Utilization

    NASA Astrophysics Data System (ADS)

    Wang, Y.

    2015-12-01

    A reasonable floodwater resources utilization method is put forward by dynamic controlling of cascade reservoirs flood control limited level in this paper. According to the probability distribution of the beginning time of the first flood and the ending time of the final flood from July to September, the Fuzzy Statistic Analysis was used to divide the main flood season. By fitting the flood season membership functions of each period, the cascade reservoirs flood control limited water level for each period were computed according to the characteristic data of reservoirs. In terms of the benefit maximization and risk minimum principle, the reasonable combination of flood control limited water level of cascade reservoirs was put forward.

  8. Fully analogue photonic reservoir computer.

    PubMed

    Duport, François; Smerieri, Anteo; Akrout, Akram; Haelterman, Marc; Massar, Serge

    2016-03-03

    Introduced a decade ago, reservoir computing is an efficient approach for signal processing. State of the art capabilities have already been demonstrated with both computer simulations and physical implementations. If photonic reservoir computing appears to be promising a solution for ultrafast nontrivial computing, all the implementations presented up to now require digital pre or post processing, which prevents them from exploiting their full potential, in particular in terms of processing speed. We address here the possibility to get rid simultaneously of both digital pre and post processing. The standalone fully analogue reservoir computer resulting from our endeavour is compared to previous experiments and only exhibits rather limited degradation of performances. Our experiment constitutes a proof of concept for standalone physical reservoir computers.

  9. Reservoir evaporation in Texas, USA

    NASA Astrophysics Data System (ADS)

    Wurbs, Ralph A.; Ayala, Rolando A.

    2014-03-01

    The role of reservoir surface evaporation in river/reservoir water budgets and water management is explored using a modeling system that combines historical natural hydrology with current conditions of water resources development and management. The long-term mean evaporation from the 3415 reservoirs in the Texas water rights permit system is estimated to be 7.53 billion m3/year, which is equivalent to 61% of total agricultural or 126% of total municipal water use in the state during the year 2010. Evaporation varies with the hydrologic conditions governing reservoir surface areas and evaporation rates. Annual statewide total evaporation volumes associated with exceedance probabilities of 75%, 50%, and 25% are 7.07, 7.47, and 7.95 billion m3/year, respectively. Impacts of evaporation are greatest during extended severe droughts that govern water supply capabilities.

  10. Fully analogue photonic reservoir computer

    PubMed Central

    Duport, François; Smerieri, Anteo; Akrout, Akram; Haelterman, Marc; Massar, Serge

    2016-01-01

    Introduced a decade ago, reservoir computing is an efficient approach for signal processing. State of the art capabilities have already been demonstrated with both computer simulations and physical implementations. If photonic reservoir computing appears to be promising a solution for ultrafast nontrivial computing, all the implementations presented up to now require digital pre or post processing, which prevents them from exploiting their full potential, in particular in terms of processing speed. We address here the possibility to get rid simultaneously of both digital pre and post processing. The standalone fully analogue reservoir computer resulting from our endeavour is compared to previous experiments and only exhibits rather limited degradation of performances. Our experiment constitutes a proof of concept for standalone physical reservoir computers. PMID:26935166

  11. Functional wettability in carbonate reservoirs

    DOE PAGES

    Brady, Patrick V.; Thyne, Geoffrey

    2016-10-11

    Oil adsorbs to carbonate reservoirs indirectly through a relatively thick separating water layer, and directly to the surface through a relatively thin intervening water layer. Whereas directly sorbed oil desorbs slowly and incompletely in response to changes in reservoir conditions, indirectly sorbed oil can be rapidly desorbed by changing the chemistry of the separating water layer. The additional recovery might be as much as 30% original oil in place (OOIP) above the ~30% OOIP recovered from carbonates through reservoir depressurization (primary production) and viscous displacement (waterflooding). Electrostatic adhesive forces are the dominant control over carbonate reservoir wettability. A surface complexationmore » model that quantifies electrostatic adhesion accurately predicts oil recovery trends for carbonates. Furthermore, the approach should therefore be useful for estimating initial wettability and designing fluids that improve oil recovery.« less

  12. Functional wettability in carbonate reservoirs

    SciTech Connect

    Brady, Patrick V.; Thyne, Geoffrey

    2016-10-11

    Oil adsorbs to carbonate reservoirs indirectly through a relatively thick separating water layer, and directly to the surface through a relatively thin intervening water layer. Whereas directly sorbed oil desorbs slowly and incompletely in response to changes in reservoir conditions, indirectly sorbed oil can be rapidly desorbed by changing the chemistry of the separating water layer. The additional recovery might be as much as 30% original oil in place (OOIP) above the ~30% OOIP recovered from carbonates through reservoir depressurization (primary production) and viscous displacement (waterflooding). Electrostatic adhesive forces are the dominant control over carbonate reservoir wettability. A surface complexation model that quantifies electrostatic adhesion accurately predicts oil recovery trends for carbonates. Furthermore, the approach should therefore be useful for estimating initial wettability and designing fluids that improve oil recovery.

  13. Unraveling Host-Vector-Arbovirus Interactions by Two-Gene High Resolution Melting Mosquito Bloodmeal Analysis in a Kenyan Wildlife-Livestock Interface

    PubMed Central

    Omondi, David; Masiga, Daniel K.; Ajamma, Yvonne Ukamaka; Fielding, Burtram C.; Njoroge, Laban; Villinger, Jandouwe

    2015-01-01

    The blood-feeding patterns of mosquitoes are directly linked to the spread of pathogens that they transmit. Efficient identification of arthropod vector bloodmeal hosts can identify the diversity of vertebrate species potentially involved in disease transmission cycles. While molecular bloodmeal analyses rely on sequencing of cytochrome b (cyt b) or cytochrome oxidase 1 gene PCR products, recently developed bloodmeal host identification based on high resolution melting (HRM) analyses of cyt b PCR products is more cost-effective. To resolve the diverse vertebrate hosts that mosquitoes may potentially feed on in sub-Saharan Africa, we utilized HRM profiles of both cyt b and 16S ribosomal RNA genes. Among 445 blood-fed Aedeomyia, Aedes, Anopheles, Culex, Mansonia, and Mimomyia mosquitoes from Kenya’s Lake Victoria and Lake Baringo regions where many mosquito-transmitted pathogens are endemic, we identified 33 bloodmeal hosts including humans, eight domestic animal species, six peridomestic animal species and 18 wildlife species. This resolution of vertebrate host species was only possible by comparing profiles of both cyt b and 16S markers, as melting profiles of some pairs of species were similar for either marker but not both. We identified mixed bloodmeals in a Culex pipiens from Mbita that had fed on a goat and a human and in two Mansonia africana mosquitoes from Baringo that each had fed on a rodent (Arvicanthis niloticus) in addition to a human or baboon. We further detected Sindbis and Bunyamwera viruses in blood-fed mosquito homogenates by Vero cell culture and RT-PCR in Culex, Aedeomyia, Anopheles and Mansonia mosquitoes from Baringo that had fed on humans and livestock. The observed mosquito feeding on both arbovirus amplifying hosts (including sheep and goats) and possible arbovirus reservoirs (birds, porcupine, baboons, rodents) informs arbovirus disease epidemiology and vector control strategies. PMID:26230507

  14. 33 CFR 211.81 - Reservoir areas.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... McClellan-Kerr Navigation Project in Oklahoma, to Former Owners Authority: Secs. 211.101 to 211.111... to: (a) Fort Gibson Reservoir Area, Oklahoma. (b) Lake Texoma and the Denison Reservoir Area..., Nebraska. (e) Fort Randall Reservoir Area, South Dakota. (f) Garrison Reservoir Area, North Dakota....

  15. 33 CFR 211.81 - Reservoir areas.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... McClellan-Kerr Navigation Project in Oklahoma, to Former Owners Authority: Secs. 211.101 to 211.111... to: (a) Fort Gibson Reservoir Area, Oklahoma. (b) Lake Texoma and the Denison Reservoir Area..., Nebraska. (e) Fort Randall Reservoir Area, South Dakota. (f) Garrison Reservoir Area, North Dakota....

  16. 33 CFR 211.81 - Reservoir areas.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... McClellan-Kerr Navigation Project in Oklahoma, to Former Owners Authority: Secs. 211.101 to 211.111... to: (a) Fort Gibson Reservoir Area, Oklahoma. (b) Lake Texoma and the Denison Reservoir Area..., Nebraska. (e) Fort Randall Reservoir Area, South Dakota. (f) Garrison Reservoir Area, North Dakota....

  17. 33 CFR 211.81 - Reservoir areas.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... McClellan-Kerr Navigation Project in Oklahoma, to Former Owners Authority: Secs. 211.101 to 211.111... to: (a) Fort Gibson Reservoir Area, Oklahoma. (b) Lake Texoma and the Denison Reservoir Area..., Nebraska. (e) Fort Randall Reservoir Area, South Dakota. (f) Garrison Reservoir Area, North Dakota....

  18. 49 CFR 393.50 - Reservoirs required.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 5 2014-10-01 2014-10-01 false Reservoirs required. 393.50 Section 393.50... NECESSARY FOR SAFE OPERATION Brakes § 393.50 Reservoirs required. (a) Reservoir capacity for air-braked... trailers manufactured on or after January 1, 1975, must meet the reservoir requirements of FMVSS No....

  19. Chickamauga reservoir embayment study - 1990

    SciTech Connect

    Meinert, D.L.; Butkus, S.R.; McDonough, T.A.

    1992-12-01

    The objectives of this report are three-fold: (1) assess physical, chemical, and biological conditions in the major embayments of Chickamauga Reservoir; (2) compare water quality and biological conditions of embayments with main river locations; and (3) identify any water quality concerns in the study embayments that may warrant further investigation and/or management actions. Embayments are important areas of reservoirs to be considered when assessments are made to support water quality management plans. In general, embayments, because of their smaller size (water surface areas usually less than 1000 acres), shallower morphometry (average depth usually less than 10 feet), and longer detention times (frequently a month or more), exhibit more extreme responses to pollutant loadings and changes in land use than the main river region of the reservoir. Consequently, embayments are often at greater risk of water quality impairments (e.g. nutrient enrichment, filling and siltation, excessive growths of aquatic plants, algal blooms, low dissolved oxygen concentrations, bacteriological contamination, etc.). Much of the secondary beneficial use of reservoirs occurs in embayments (viz. marinas, recreation areas, parks and beaches, residential development, etc.). Typically embayments comprise less than 20 percent of the surface area of a reservoir, but they often receive 50 percent or more of the water-oriented recreational use of the reservoir. This intensive recreational use creates a potential for adverse use impacts if poor water quality and aquatic conditions exist in an embayment.

  20. SMALL, GEOLOGICALLY COMPLEX RESERVOIRS CAN BENEFIT FROM RESERVOIR SIMULATION

    SciTech Connect

    Richard E. Bennett

    2002-06-24

    The Cascade Sand zone of the Mission-Visco Lease in the Cascade Oil field of Los Angeles County, California, has been under water flood since 1970. Increasing water injection to increase oil production rates was being considered as an opportunity to improve oil recovery. However, a secondary gas cap had formed in the up-dip portion of the reservoir with very low gas cap pressures, creating concern that oil could be displaced into the gas cap resulting in the loss of recoverable oil. Therefore, injecting gas into the gas cap to keep the gas cap pressurized and restrict the influx of oil during water injection was also being considered. Further, it was recognized that the reservoir geology in the gas cap area is very complex with numerous folding and faulting and thus there are potential pressure barriers in several locations throughout the reservoir. With these conditions in mind, there were concerns regarding well to well continuity in the gas cap, which could interfere with the intended repressurization impact. Concerns about the pattern of gas flow from well to well, the possibilities of cycling gas without the desired increased pressure, and the possible loss of oil displaced into the gas cap resulted in the decision to conduct a gas tracer survey in an attempt to better define inter-well communication. Following the gas tracer survey, a reservoir model would be developed to integrate the findings of the gas tracer survey, known geologic and reservoir data, and historic production data. The reservoir model would be used to better define the reservoir characteristics and provide information that could help optimize the waterflood-gas injection project under consideration for efficient water and gas injection management to increase oil production. However, due to inadequate gas sampling procedures in the field and insufficiently developed laboratory analytical techniques, the laboratory was unable to detect the tracer in the gas samples taken. At that point, focus

  1. Influence of Host Ecology and Behavior on Campylobacter jejuni Prevalence and Environmental Contamination Risk in a Synanthropic Wild Bird Species

    PubMed Central

    Weis, Allison M.; Wheeler, Sarah; Hinton, Mitchell G.; Weimer, Bart C.; Barker, Christopher M.; Jones, Melissa; Logsdon, Ryane; Smith, Woutrina A.; Boyce, Walter M.; Townsend, Andrea K.

    2016-01-01

    ABSTRACT Campylobacter jejuni is a foodborne pathogen that often leads to human infections through the consumption of contaminated poultry. Wild birds may play a role in the transmission of C. jejuni by acting as reservoir hosts. Despite ample evidence that wild birds harbor C. jejuni, few studies have addressed the role of host ecology in transmission to domestic animals or humans. We tested the hypothesis that host social behavior and habitat play a major role in driving transmission risk. C. jejuni infection and host ecology were studied simultaneously in wild American crows (Corvus brachyrhynchos) in Davis, CA, over 3 years. We found that 178 of 337 samples tested were culture positive (53%), with infection varying by season and host age. Among adult crows, infection rates were highest during the winter, when migrants return and crows form large communal roosts. Nestlings had the highest risk of infection, and whole-genome sequencing supports the observation of direct transmission between nestlings. We deployed global positioning system (GPS) receivers to quantify habitat use by crows; space use was nonrandom, with crows preferentially occupying some habitats while avoiding others. This behavior drastically amplified the risk of environmental contamination from feces in specific locations. This study demonstrates that social behavior contributes to infection within species and that habitat use leads to a heterogeneous risk of cross-species transmission. IMPORTANCE Campylobacter jejuni is the most common cause of gastroenteritis in industrialized countries. Despite efforts to reduce the colonization of poultry flocks and eventual infection of humans, the incidence of human C. jejuni infection has remained high. Because wild birds can harbor strains of C. jejuni that eventually infect humans, there has long been speculation that wild birds might act as an important reservoir in the C. jejuni infection cycle. We simultaneously studied infection prevalence, social

  2. Host defenses against cryptococcosis.

    PubMed

    Price, Michael S; Perfect, John R

    2011-01-01

    The interaction of pathogenic Cryptococcus species with their various hosts is somewhat unique compared to other fungal pathogens such as Aspergillus fumigatus and Candida albicans. Cryptococcus shares an intimate association with host immune cells, leading to enhanced intracellular growth. Furthermore, unlike most other fungal pathogens, the signs and symptoms of cryptococcal disease are typically self-inflicted by the host during the host's attempt to clear this invader from sensitive organ systems such as the central nervous system. In this review, we will summarize the story of host-Cryptococcus interactions to date and explore strategies to exploit the current knowledge for treatment of cryptococcal infections.

  3. Animal Testing

    NASA Astrophysics Data System (ADS)

    Moretto, Johnny; Chauffert, Bruno; Bouyer, Florence

    The development of a new anticancer drug is a long, complex and multistep process which is supervised by regulatory authorities from the different countries all around the world [1]. Application of a new drug for admission to the market is supported by preclinical and clinical data, both including the determination of pharmacodynamics, toxicity, antitumour activity, therapeutic index, etc. As preclinical studies are associated with high cost, optimization of animal experiments is crucial for the overall development of a new anticancer agent. Moreover, in vivo efficacy studies remain a determinant panel for advancement of agents to human trials and thus, require cautious design and interpretation from experimental and ethical point of views.

  4. Petroleum reservoir data for testing simulation models

    SciTech Connect

    Lloyd, J.M.; Harrison, W.

    1980-09-01

    This report consists of reservoir pressure and production data for 25 petroleum reservoirs. Included are 5 data sets for single-phase (liquid) reservoirs, 1 data set for a single-phase (liquid) reservoir with pressure maintenance, 13 data sets for two-phase (liquid/gas) reservoirs and 6 for two-phase reservoirs with pressure maintenance. Also given are ancillary data for each reservoir that could be of value in the development and validation of simulation models. A bibliography is included that lists the publications from which the data were obtained.

  5. Reservoir characterization of Pennsylvanian Sandstone Reservoirs. Annual report

    SciTech Connect

    Kelkar, M.

    1992-09-01

    This annual report describes the progress during the second year of a project on Reservoir Characterization of Pennsylvanian Sandstone Reservoirs. The report is divided into three sections: (i) reservoir description and scale-up procedures; (ii) outcrop investigation; (iii) in-fill drilling potential. The first section describes the methods by which a reservoir can be characterized, can be described in three dimensions, and can be scaled up with respect to its properties, appropriate for simulation purposes. The second section describes the progress on investigation of an outcrop. The outcrop is an analog of Bartlesville Sandstone. We have drilled ten wells behind the outcrop and collected extensive log and core data. The cores have been slabbed, photographed and the several plugs have been taken. In addition, minipermeameter is used to measure permeabilities on the core surface at six inch intervals. The plugs have been analyzed for the permeability and porosity values. The variations in property values will be tied to the geological descriptions as well as the subsurface data collected from the Glen Pool field. The third section discusses the application of geostatistical techniques to infer in-fill well locations. The geostatistical technique used is the simulated annealing technique because of its flexibility. One of the important reservoir data is the production data. Use of production data will allow us to define the reservoir continuities, which may in turn, determine the in-fill well locations. The proposed technique allows us to incorporate some of the production data as constraints in the reservoir descriptions. The technique has been validated by comparing the results with numerical simulations.

  6. Evidence for the survival of the oldest terrestrial mantle reservoir.

    PubMed

    Jackson, Matthew G; Carlson, Richard W; Kurz, Mark D; Kempton, Pamela D; Francis, Don; Blusztajn, Jerzy

    2010-08-12

    Helium is a powerful tracer of primitive material in Earth's mantle. Extremely high (3)He/(4)He ratios in some ocean-island basalts suggest the presence of relatively undegassed and undifferentiated material preserved in Earth's mantle. However, terrestrial lavas with high (3)He/(4)He ratios have never been observed to host the primitive lead-isotopic compositions that are required for an early (roughly 4.5 Gyr ago) formation age. Here we show that Cenozoic-era Baffin Island and West Greenland lavas, previously found to host the highest terrestrial-mantle (3)He/(4)He ratios, exhibit primitive lead-isotope ratios that are consistent with an ancient mantle source age of 4.55-4.45 Gyr. The Baffin Island and West Greenland lavas also exhibit (143)Nd/(144)Nd ratios similar to values recently proposed for an early-formed (roughly 4.5 Gyr ago) terrestrial mantle reservoir. The combined helium-, lead- and Nd-isotopic compositions in Baffin Island and West Greenland lavas therefore suggest that their source is the most ancient accessible reservoir in the Earth's mantle, and it may be parental to all mantle reservoirs that give rise to modern volcanism.

  7. Foodborne Campylobacter: Infections, Metabolism, Pathogenesis and Reservoirs

    PubMed Central

    Epps, Sharon V. R.; Harvey, Roger B.; Hume, Michael E.; Phillips, Timothy D.; Anderson, Robin C.; Nisbet, David J.

    2013-01-01

    Campylobacter species are a leading cause of bacterial-derived foodborne illnesses worldwide. The emergence of this bacterial group as a significant causative agent of human disease and their propensity to carry antibiotic resistance elements that allows them to resist antibacterial therapy make them a serious public health threat. Campylobacter jejuni and Campylobacter coli are considered to be the most important enteropathogens of this genus and their ability to colonize and survive in a wide variety of animal species and habitats make them extremely difficult to control. This article reviews the historical and emerging importance of this bacterial group and addresses aspects of the human infections they cause, their metabolism and pathogenesis, and their natural reservoirs in order to address the need for appropriate food safety regulations and interventions. PMID:24287853

  8. The Ogden Valley artesian reservoir

    USGS Publications Warehouse

    Thomas, H.E.

    1945-01-01

    Ogden Valley, in Weber County, Utah, contains an artesian reservoir from which the city of Ogden obtains all except a small part of its municipal water supply. A detailed investigation of the ground-water resources of Ogden Valley, and particularly of this artesian reservoir, was made by the Geological Survey, United States Department of the Interior, in cooperation with the city of Ogden between 1932 and 1934, and the results of this investigation have been reported by Leggette and Taylor.1 The present paper, which might be termed a sequel to that report, is based on data collected during those years, augmented by records that have been obtained (1935-1940) by the Geological Survey as part of a State-wide project in cooperation with the Utah State Engineer. The conclusions drawn from the study of these records and presented in detail in the following pages are as follows: (1) The artesian reservoir is filled to capacity nearly every year during the spring run-off from melting snow; (2) after the annual freshet, the recharge to the reservoir is insufficient to balance the discharge from artesian wells, which ordinarily is at a maximum during the summer; the reservoir is depleted and is not filled again until the following spring; (3) during the periods when the artesian reservoir is not full the rate of recharge is more or less proportional to the inflow to the valley by streams, except that rain on the recharge area may be of sufficient intensity to contribute some water by infiltration and deep penetration; and (4) the artesian reservoir thus serves to store water that would otherwise be lost to Great Salt Lake in the excess spring overflow, and available records indicate that water used by increased draft from wells would be replenished in normal years by increased recharge during the spring freshet.

  9. Role of myeloid cells in HIV-1-host interplay.

    PubMed

    Stevenson, Mario

    2015-06-01

    The AIDS research field has embarked on a bold mission to cure HIV-1-infected individuals of the virus. To do so, scientists are attempting to identify the reservoirs that support viral persistence in patients on therapy, to understand how viral persistence is regulated and to come up with strategies that interrupt viral persistence and that eliminate the viral reservoirs. Most of the attention regarding the cure of HIV-1 infection has focused on the CD4+ T cell reservoir. Investigators are developing tools to probe the CD4+ T cell reservoirs as well as in vitro systems that provide clues on how to perturb them. By comparison, the myeloid cell, and in particular, the macrophage has received far less attention. As a consequence, there is very little understanding as to the role played by myeloid cells in viral persistence in HIV-1-infected individuals on suppressive therapy. As such, should myeloid cells constitute a viral reservoir, unique strategies may be required for their elimination. This article will overview research that is examining the role of macrophage in virus-host interplay and will discuss features of this interplay that could impact efforts to eliminate myeloid cell reservoirs.

  10. [Parasite-host relationships and treatment].

    PubMed

    Vuitton, Dominique-Angèle; Mantion, Georges; Bartholomot, Brigitte; Giraudoux, Patrick; Bresson-Hadni, Solange

    2008-01-01

    Alveolar echinococcosis (AE) is a parasitic disease caused by intrahepatic growth of the larval stage of the cestode Echinococcus multilocularis. The main definitive host in Europe is the fox. The adult worms live in the fox intestine and their oncospheres are disseminated by faeces. Wolves, dogs and cats may also serve as definitive hosts. Small rodents--especially voles in Europe and small lagomorphs in Asia--are the natural intermediate hosts. The tumour-like larva is composed of multiple vesicles which produce protoscoleces, the fertile stage of the E. multilocularis metacestode. Carnivores are infected by preying on infected rodents. Like rodents, humans are intermediate hosts and are infected either by eating uncooked vegetables and berries contaminated by faeces of infected carnivores, or by touching such animals. Humans are naturally resistant to metacestode development. Genetic characteristics are involved in susceptibility/resistance to E. multilocularis metacestodes. In humans and other intermediate animal hosts, immune suppression enhances parasite growth, which is normally controlled by cytotoxic mechanisms and delayed-type hypersensitivity. Tolerance of E. multilocularis is due in part to parasite characteristics (especially carbohydrate antigens of the laminated layer) and in part to the "anti-inflammatory/tolerogenic" cytokines IL-10 and TGF-beta. Treatment with interferon-a restores a cytokine balance favorable to the host and might be a new therapeutic option for AE patients. Vaccination is a scientifically sound but economically and politically Utopian means of preventing the disease. Prevention thus relies on simple lifestyle measures: cooking potentially contaminated food, regular treatment of domestic animals with praziquantel, and precautions when touching potentially infected definitive hosts (foxes and dogs).

  11. No Serological Evidence that Harbour Porpoises Are Additional Hosts of Influenza B Viruses

    PubMed Central

    Bodewes, Rogier; van de Bildt, Marco W. G.; van Elk, Cornelis E.; Bunskoek, Paulien E.; van de Vijver, David A. M. C.; Smits, Saskia L.; Osterhaus, Albert D. M. E.; Kuiken, Thijs

    2014-01-01

    Influenza A and B viruses circulate among humans causing epidemics almost annually. While various hosts for influenza A viruses exist, influenza B viruses have been detected only in humans and seals. However, recurrent infections of seals in Dutch coastal waters with influenza B viruses that are antigenetically distinct from influenza B viruses circulating among humans suggest that influenza B viruses have been introduced into this seal population by another, non-human, host. Harbour porpoises (Phocoena phocoena) are sympatric with seals in these waters and are also occasionally in close contact with humans after stranding and subsequent rehabilitation. In addition, virus attachment studies demonstrated that influenza B viruses can bind to cells of the respiratory tract of these animals. Therefore, we hypothesized that harbour porpoises might be a reservoir of influenza B viruses. In the present study, an unique set of serum samples from 79 harbour porpoises, stranded alive on the Dutch coast between 2003 and 2013, was tested for the presence of antibodies against influenza B viruses by use of the hemagglutination inhibition test and for antibodies against influenza A viruses by use of a competitive influenza A nucleoprotein ELISA. No antibodies were detected against either virus, suggesting that influenza A and B virus infections of harbour porpoises in Dutch coastal waters are not common, which was supported by statistical analysis of the dataset. PMID:24551217

  12. A comparison of bats and rodents as reservoirs of zoonotic viruses: are bats special?

    USGS Publications Warehouse

    Luis, Angela D.; Hayman, David T.S.; O'Shea, Thomas J.; Cryan, Paul M.; Gilbert, Amy T.; Pulliam, Juliet R.C.; Mills, James N.; Timonin, Mary E.; Willis, Craig K.R.; Cunningham, Andrew A.; Fooks, Anthony R.; Rupprecht, Charles E.; Wood, James L.N.; Webb, Colleen T.

    2013-01-01

    Bats are the natural reservoirs of a number of high-impact viral zoonoses. We present a quantitative analysis to address the hypothesis that bats are unique in their propensity to host zoonotic viruses based on a comparison with rodents, another important host order. We found that bats indeed host more zoonotic viruses per species than rodents, and we identified life-history and ecological factors that promote zoonotic viral richness. More zoonotic viruses are hosted by species whose distributions overlap with a greater number of other species in the same taxonomic order (sympatry). Specifically in bats, there was evidence for increased zoonotic viral richness in species with smaller litters (one young), greater longevity and more litters per year. Furthermore, our results point to a new hypothesis to explain in part why bats host more zoonotic viruses per species: the stronger effect of sympatry in bats and more viruses shared between bat species suggests that interspecific transmission is more prevalent among bats than among rodents. Although bats host more zoonotic viruses per species, the total number of zoonotic viruses identified in bats (61) was lower than in rodents (68), a result of there being approximately twice the number of rodent species as bat species. Therefore, rodents should still be a serious concern as reservoirs of emerging viruses. These findings shed light on disease emergence and perpetuation mechanisms and may help lead to a predictive framework for identifying future emerging infectious virus reservoirs.

  13. A comparison of bats and rodents as reservoirs of zoonotic viruses: are bats special?

    PubMed Central

    Luis, Angela D.; Hayman, David T. S.; O'Shea, Thomas J.; Cryan, Paul M.; Gilbert, Amy T.; Pulliam, Juliet R. C.; Mills, James N.; Timonin, Mary E.; Willis, Craig K. R.; Cunningham, Andrew A.; Fooks, Anthony R.; Rupprecht, Charles E.; Wood, James L. N.; Webb, Colleen T.

    2013-01-01

    Bats are the natural reservoirs of a number of high-impact viral zoonoses. We present a quantitative analysis to address the hypothesis that bats are unique in their propensity to host zoonotic viruses based on a comparison with rodents, another important host order. We found that bats indeed host more zoonotic viruses per species than rodents, and we identified life-history and ecological factors that promote zoonotic viral richness. More zoonotic viruses are hosted by species whose distributions overlap with a greater number of other species in the same taxonomic order (sympatry). Specifically in bats, there was evidence for increased zoonotic viral richness in species with smaller litters (one young), greater longevity and more litters per year. Furthermore, our results point to a new hypothesis to explain in part why bats host more zoonotic viruses per species: the stronger effect of sympatry in bats and more viruses shared between bat species suggests that interspecific transmission is more prevalent among bats than among rodents. Although bats host more zoonotic viruses per species, the total number of zoonotic viruses identified in bats (61) was lower than in rodents (68), a result of there being approximately twice the number of rodent species as bat species. Therefore, rodents should still be a serious concern as reservoirs of emerging viruses. These findings shed light on disease emergence and perpetuation mechanisms and may help lead to a predictive framework for identifying future emerging infectious virus reservoirs. PMID:23378666

  14. [Cats and dogs as a reservoir for Staphylococcus aureus].

    PubMed

    Bierowiec, Karolina; Płoneczka-Janeczko, Katarzyna; Rypuła, Krzysztof

    2014-08-18

    For many years, Staphylococcus aureus MRSA was thought to happen only in humans. It has now become an increasingly urgent problem in veterinary medicine, with MRSA infections reported in pets as well as farm animals. The animals may be contaminated, colonized or infected with MSSA as well as MRSA strains. Pets are a potential reservoir for human infection. Transmission of such pathogen occurs between pets, owners and veterinary staff. This is why, is need to generate data regarding both the levels of carriage of such bacteria in pets and the risk factors associated with the transfer of the bacteria to humans, who have a contact with infected pets.

  15. The Microbiome and Host Behavior.

    PubMed

    Vuong, Helen E; Yano, Jessica M; Fung, Thomas C; Hsiao, Elaine Y

    2017-03-08

    The microbiota is increasingly recognized for its ability to influence the development and function of the nervous system and several complex host behaviors. In this review, we discuss emerging roles for the gut microbiota in modulating host social and communicative behavior, stressor-induced behavior, and performance in learning and memory tasks. We summarize effects of the microbiota on host neurophysiology, including brain microstructure, gene expression, and neurochemical metabolism across regions of the amygdala, hippocampus, frontal cortex, and hypothalamus. We further assess evidence linking dysbiosis of the gut microbiota to neurobehavioral diseases, such as autism spectrum disorder and major depression, drawing upon findings from animal models and human trials. Finally, based on increasing associations between the microbiota, neurophysiology, and behavior, we consider whether investigating mechanisms underlying the microbiota-gut-brain axis could lead to novel approaches for treating particular neurological conditions. Expected final online publication date for the Annual Review of Neuroscience Volume 40 is July 8, 2017. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

  16. Communication between Bacteria and Their Hosts

    PubMed Central

    2013-01-01

    It is clear that a dialogue is occurring between microbes and their hosts and that chemical signals are the language of this interkingdom communication. Microbial endocrinology shows that, through their long coexistence with animals and plants, microorganisms have evolved sensors for detecting eukaryotic hormones, which the microbe uses to determine that they are within proximity of a suitable host and to optimally time the expression of genes needed for host colonisation. It has also been shown that some prokaryotic chemical communication signals are recognized by eukaryotes. Deciphering what is being said during the cross-talk between microbe and host is therefore important, as it could lead to new strategies for preventing or treating bacterial infections. PMID:24381789

  17. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    SciTech Connect

    1998-01-01

    Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations.

  18. Application of Integrated Reservoir management and Reservoir Characterization to Optimize Infill Drilling

    SciTech Connect

    B. Pregger; D. Davies; D. Moore; G. Freeman; J. Callard; J.W. Nevans; L. Doublet; R. Vessell; T. Blasingame

    1997-08-31

    Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations.

  19. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    SciTech Connect

    1998-03-12

    Infill drilling if wells on a uniform spacing without regard to reservoir performance and characterization foes not optimize reservoir development because it fails to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. New and emerging technologies, such as geostatistical modeling, rigorous decline curve analysis, reservoir rock typing, and special core analysis can be used to develop a 3-D simulation model for prediction of infill locations.

  20. Bioethical Problems: Animal Welfare, Animal Rights.

    ERIC Educational Resources Information Center

    March, B. E.

    1984-01-01

    Discusses various bioethical issues and problems related to animal welfare and animal rights. Areas examined include: Aristotelian views; animal welfare legislation; Darwin and evolutionary theory; animal and human behavior; and vegetarianism. A 14-point universal declaration of the rights of animals is included. (JN)

  1. Host Pathogen Relations: Exploring Animal Models for Fungal Pathogens

    PubMed Central

    Harwood, Catherine G.; Rao, Reeta P.

    2014-01-01

    Pathogenic fungi cause superficial infections but pose a significant public health risk when infections spread to deeper tissues, such as the lung. Within the last three decades, fungi have been identified as the leading cause of nosocomial infections making them the focus of research. This review outlines the model systems such as the mouse, zebrafish larvae, flies, and nematodes, as well as ex vivo and in vitro systems available to study common fungal pathogens. PMID:25438011

  2. HOST DEFENSE AGAINST BACTERIAL ENDOTOXEMIA: MECHANISM IN NORMAL ANIMALS

    PubMed Central

    Skarnes, Robert C.

    1970-01-01

    The present study defines the early response of normal rabbits to the intravenous injection of a single, sublethal dose of endotoxin. Within the first few hours following endotoxin there occurs in the circulating plasma of recipients a decrease in ionized calcium, a threefold increase in the heat-stable, organo-phosphate-resistant esterase level, and a striking increase in the endotoxin-detoxifying capacity. These results are fully consistent with the thesis that circulating plasma represents a principal site of detoxification and that plasma esterases of the nonspecific, carboxylic type are of major concern in defense against circulating endotoxins. PMID:4994446

  3. Glob-Hosts

    SciTech Connect

    Behlendorf, B.; Garlick, J.

    2007-08-31

    The glob-hosts utility manipulates hostlist strings in UNIX shell scripts. Hostlists are a parseable string representatin of list of hosts, which compress nicely when a group of hosts are named with contiguous numeric suffixes. For example, the hosts blue1, blue2, and blue3 can be represented by the hostlist string "blue1, blue2, blue3" or equivalently "blue[1-3]". The globhost utility cn peform the following operations on a hostlist string: count, size, expand, nth, union, minus, intersection, and exclude.

  4. Bioturbating animals control the mobility of redox-sensitive trace elements in organic-rich mudstone

    SciTech Connect

    Harazim, Dario; McIlroy, Duncan; Edwards, Nicholas P.; Wogelius, Roy A.; Manning, Phillip L.; Poduska, Kristin M.; Layne, Graham D.; Sokaras, Dimosthenis; Alonso-Mori, Roberto; Bergmann, Uwe

    2015-10-07

    Bioturbating animals modify the original mineralogy, porosity, organic content, and fabric of mud, thus affecting the burial diagenetic pathways of potential hydrocarbon source, seal, and reservoir rocks. High-sensitivity, synchrotron rapid scanning X-ray fluorescence elemental mapping reveals that producers of phycosiphoniform burrows systematically partition redox-sensitive trace elements (i.e., Fe, V, Cr, Mn, Co, Ni, Cu, and As) in fine-grained siliciclastic rocks. Systematic differences in organic carbon content (total organic carbon >1.5 wt%) and quality (Δ13Corg~0.6‰) are measured between the burrow core and host sediment. The relative enrichment of redox-sensitive elements in the burrow core does not correlate with significant neo-formation of early diagenetic pyrite (via trace metal pyritization), but is best explained by physical concentration of clay- and silt-sized components. A measured loss (~–15%) of the large-ionic-radius elements Sr and Ba from both burrow halo and core is most likely associated with the release of Sr and Ba to pore waters during biological (in vivo) weathering of silt- to clay-sized lithic components and feldspar. In conclusion, this newly documented effect has significant potential to inform the interpretation of geochemical proxy and rock property data, particularly from shales, where elemental analyses are commonly employed to predict reservoir quality and support paleoenvironmental analysis.

  5. Bioturbating animals control the mobility of redox-sensitive trace elements in organic-rich mudstone

    DOE PAGES

    Harazim, Dario; McIlroy, Duncan; Edwards, Nicholas P.; ...

    2015-10-07

    Bioturbating animals modify the original mineralogy, porosity, organic content, and fabric of mud, thus affecting the burial diagenetic pathways of potential hydrocarbon source, seal, and reservoir rocks. High-sensitivity, synchrotron rapid scanning X-ray fluorescence elemental mapping reveals that producers of phycosiphoniform burrows systematically partition redox-sensitive trace elements (i.e., Fe, V, Cr, Mn, Co, Ni, Cu, and As) in fine-grained siliciclastic rocks. Systematic differences in organic carbon content (total organic carbon >1.5 wt%) and quality (Δ13Corg~0.6‰) are measured between the burrow core and host sediment. The relative enrichment of redox-sensitive elements in the burrow core does not correlate with significant neo-formation ofmore » early diagenetic pyrite (via trace metal pyritization), but is best explained by physical concentration of clay- and silt-sized components. A measured loss (~–15%) of the large-ionic-radius elements Sr and Ba from both burrow halo and core is most likely associated with the release of Sr and Ba to pore waters during biological (in vivo) weathering of silt- to clay-sized lithic components and feldspar. In conclusion, this newly documented effect has significant potential to inform the interpretation of geochemical proxy and rock property data, particularly from shales, where elemental analyses are commonly employed to predict reservoir quality and support paleoenvironmental analysis.« less

  6. Application of Integrated Reservoir Management and Reservoir Characterization to Optimize Infill Drilling

    SciTech Connect

    P. K. Pande

    1998-10-29

    Initial drilling of wells on a uniform spacing, without regard to reservoir performance and characterization, must become a process of the past. Such efforts do not optimize reservoir development as they fail to account for the complex nature of reservoir heterogeneities present in many low permeability reservoirs, and carbonate reservoirs in particular. These reservoirs are typically characterized by: o Large, discontinuous pay intervals o Vertical and lateral changes in reservoir properties o Low reservoir energy o High residual oil saturation o Low recovery efficiency

  7. Algae as Reservoirs for Coral Pathogens

    PubMed Central

    Sweet, Michael J.; Bythell, John C.; Nugues, Maggy M.

    2013-01-01

    Benthic algae are associated with coral death in the form of stress and disease. It's been proposed that they release exudates, which facilitate invasion of potentially pathogenic microbes at the coral-algal interface, resulting in coral disease. However, the original source of these pathogens remains unknown. This study examined the ability of benthic algae to act as reservoirs of coral pathogens by characterizing surface associated microbes associated with major Caribbean and Indo-Pacific algal species/types and by comparing them to potential pathogens of two dominant coral diseases: White Syndrome (WS) in the Indo-Pacific and Yellow Band Disease (YBD) in the Caribbean. Coral and algal sampling was conducted simultaneously at the same sites to avoid spatial effects. Potential pathogens were defined as those absent or rare in healthy corals, increasing in abundance in healthy tissues adjacent to a disease lesion, and dominant in disease lesions. Potentially pathogenic bacteria were detected in both WS and YBD and were also present within the majority of algal species/types (54 and 100% for WS and YBD respectively). Pathogenic ciliates were associated only with WS and not YBD lesions and these were also present in 36% of the Indo-Pacific algal species. Although potential pathogens were associated with many algal species, their presence was inconsistent among replicate algal samples and detection rates were relatively low, suggestive of low density and occurrence. At the community level, coral-associated microbes irrespective of the health of their host differed from algal-associated microbes, supporting that algae and corals have distinctive microbial communities associated with their tissue. We conclude that benthic algae are common reservoirs for a variety of different potential coral pathogens. However, algal-associated microbes alone are unlikely to cause coral death. Initial damage or stress to the coral via other competitive mechanisms is most likely a

  8. Animating Brains

    PubMed Central

    Borck, Cornelius

    2016-01-01

    A recent paper famously accused the rising field of social neuroscience of using faulty statistics under the catchy title ‘Voodoo Correlations in Social Neuroscience’. This Special Issue invites us to take this claim as the starting point for a cross-cultural analysis: in which meaningful ways can recent research in the burgeoning field of functional imaging be described as, contrasted with, or simply compared to animistic practices? And what light does such a reading shed on the dynamics and effectiveness of a century of brain research into higher mental functions? Reviewing the heated debate from 2009 around recent trends in neuroimaging as a possible candidate for current instances of ‘soul catching’, the paper will then compare these forms of primarily image-based brain research with older regimes, revolving around the deciphering of the brain’s electrical activity. How has the move from a decoding paradigm to a representational regime affected the conceptualisation of self, psyche, mind and soul (if there still is such an entity)? And in what ways does modern technoscience provide new tools for animating brains? PMID:27292322

  9. Animating Brains.

    PubMed

    Borck, Cornelius

    2016-07-01

    A recent paper famously accused the rising field of social neuroscience of using faulty statistics under the catchy title 'Voodoo Correlations in Social Neuroscience'. This Special Issue invites us to take this claim as the starting point for a cross-cultural analysis: in which meaningful ways can recent research in the burgeoning field of functional imaging be described as, contrasted with, or simply compared to animistic practices? And what light does such a reading shed on the dynamics and effectiveness of a century of brain research into higher mental functions? Reviewing the heated debate from 2009 around recent trends in neuroimaging as a possible candidate for current instances of 'soul catching', the paper will then compare these forms of primarily image-based brain research with older regimes, revolving around the deciphering of the brain's electrical activity. How has the move from a decoding paradigm to a representational regime affected the conceptualisation of self, psyche, mind and soul (if there still is such an entity)? And in what ways does modern technoscience provide new tools for animating brains?

  10. Animal welfare: an animal science approach.

    PubMed

    Koknaroglu, H; Akunal, T

    2013-12-01

    Increasing world population and demand for animal-derived protein puts pressure on animal production to meet this demand. For this purpose animal breeding efforts were conducted to obtain the maximum yield that the genetic makeup of the animals permits. Under the influence of economics which is the driving force behind animal production, animal farming became more concentrated and controlled which resulted in rearing animals under confinement. Since more attention was given on economics and yield per animal, animal welfare and behavior were neglected. Animal welfare which can be defined as providing environmental conditions in which animals can display all their natural behaviors in nature started gaining importance in recent years. This does not necessarily mean that animals provided with good management practices would have better welfare conditions as some animals may be distressed even though they are in good environmental conditions. Consumers are willing to pay more for welfare-friendly products (e.g.: free range vs caged egg) and this will change the animal production practices in the future. Thus animal scientists will have to adapt themselves for the changing animal welfare rules and regulations that differ for farm animal species and countries. In this review paper, animal welfare is discussed from an animal science standpoint.

  11. Healthcare Outbreaks Associated With a Water Reservoir and Infection Prevention Strategies.

    PubMed

    Kanamori, Hajime; Weber, David J; Rutala, William A

    2016-06-01

    Hospital water may serve as a reservoir of healthcare-associated pathogens, and contaminated water can lead to outbreaks and severe infections. The clinical features of waterborne outbreaks and infections as well as prevention strategies and control measures are reviewed. The common waterborne pathogens were bacteria, including Legionella and other gram-negative bacteria, and nontuberculous mycobacteria, although fungi and viruses were occasionally described. These pathogens caused a variety of infections, including bacteremia and invasive and disseminated diseases, particularly among immunocompromised hosts and critically ill adults as well as neonates. Waterborne outbreaks occurred in healthcare settings with emergence of new reported reservoirs, including electronic faucets (Pseudomonas aeruginosa and Legionella), decorative water wall fountains (Legionella), and heater-cooler devices used in cardiac surgery (Mycobacterium chimaera). Advanced molecular techniques are useful for achieving a better understanding of reservoirs and transmission pathways of waterborne pathogens. Developing prevention strategies based on water reservoirs provides a practical approach for healthcare personnel.

  12. Towards the Elimination of Schistosomiasis japonica through Control of the Disease in Domestic Animals in The People's Republic of China: A Tale of over 60Years.

    PubMed

    Cao, Z-G; Zhao, Y-E; Lee Willingham, A; Wang, T-P

    2016-01-01

    Schistosomiasis japonica, an endemic, zoonotic tropical parasitic disease caused by Schistosoma japonicum, remains an important public health concern in The People's Republic of China. Unlike other species of Schistosoma, over 40 species of wild and domestic animals can act as reservoir hosts of S. japonicum, which increases the difficulty for the control of this tropical disease. It is widely recognized that domestic animals, particularly water buffaloes and cattle, play an important role in the transmission of S. japonicum. Hence, since the 1950s when The People's Republic of China commenced fight against the disease, the control of animal schistosomiasis has been carried out almost synchronously with that of human schistosomiasis, such that great strides have been made over the past six decades. In this chapter, we review the history and current status of schistosomiasis control in domestic animals in The People's Republic of China. We thoroughly analyse the prevalence of domestic animal schistosomiasis at different stages of schistosomiasis control and the role of different species of domestic animals in transmission of the disease, summarize the control strategies and assess their effectiveness. Furthermore, the challenges ahead are discussed and recommendations for future direction are provided.

  13. [Laboratory animal infection in modeling intestinal schistosomiasis].

    PubMed

    Zelia, O P

    1984-01-01

    A comparative efficiency of different regimes for infecting laboratory animals has been determined in order to find out optimal conditions under which an experimental model of intestinal schistosomiasis (infection with Schistosoma mansoni) can be maintained. When evaluating the results of laboratory definitive hosts infection we took into account the character of Schistosoma distribution in animals, which with high probability rate was modelled by means of negative binomial distribution. The main parameters of this distribution were used for determination of effective doses and methods of animals infection alongside with generally accepted indices of infection rate and intensiveness. Analysis of the data obtained has shown that the infection of 150 cercarians per mouse and 200 cercarians per golden and striped hairy-footed hamster by their subcutaneous administration creates optimal density of parasites in the host. Results of investigations have shown that striped hairy-footed hamsters can be used as definitive hosts of Schistosoma.

  14. Nocardia species: host-parasite relationships.

    PubMed Central

    Beaman, B L; Beaman, L

    1994-01-01

    The nocardiae are bacteria belonging to the aerobic actinomycetes. They are an important part of the normal soil microflora worldwide. The type species, Nocardia asteroides, and N. brasiliensis, N. farcinica, N. otitidiscaviarum, N. nova, and N. transvalensis cause a variety of diseases in both normal and immunocompromised humans and animals. The mechanisms of pathogenesis are complex, not fully understood, and include the capacity to evade or neutralize the myriad microbicidal activities of the host. The relative virulence of N. asteroides correlates with the ability to inhibit phagosome-lysosome fusion in phagocytes; to neutralize phagosomal acidification; to detoxify the microbicidal products of oxidative metabolism; to modify phagocyte function; to grow within phagocytic cells; and to attach to, penetrate, and grow within host cells. Both activated macrophages and immunologically specific T lymphocytes constitute the major mechanisms for host resistance to nocardial infection, whereas B lymphocytes and humoral immunity do not appear to be as important in protecting the host. Thus, the nocardiae are facultative intracellular pathogens that can persist within the host, probably in a cryptic form (L-form), for life. Silent invasion of brain cells by some Nocardia strains can induce neurodegeneration in experimental animals; however, the role of nocardiae in neurodegenerative diseases in humans needs to be investigated. Images PMID:8055469

  15. Quantification of geologic descriptions for reservoir characterization in carbonate reservoirs

    SciTech Connect

    Lucia, F.J.; Vander Stoep, G.W. )

    1990-05-01

    Recognition that a large volume of oil remains in carbonate reservoirs at the end of primary depletion and waterflooding has prompted the reevaluation of the reserve-growth potential of many existing carbonate reservoirs. Types of numerical data required include porosity, absolute permeability, relative permeability, fluid saturation, and capillary pressure, all of which are related to the size and distribution of pore space. Rock fabrics control the size and distribution of pore space and define facies that best characterize carbonate reservoirs. Thus, the link between facies descriptions and numerical engineering data is the relationship between pore-size distribution and present carbonate rock fabric. The most effective way to convert facies descriptions into engineering parameters is by considering three basic rock-fabric categories. The first category is interparticle pore space (both intergranular and intercrystalline pore types) with pore-size distribution controlled primarily by the size and shape of grains or crystals. Grain or crystal size is the key geologic measurement and, along with porosity, provides the basis for converting geologic descriptions into values for permeability, saturation, and capillarity. The second category is separate-vug pore space, such as moldic or intraparticle pore space. Separate-vug pore space adds porosity but little permeability to the reservoir rock. The contribution to saturation and capillarity depends upon the size of the separate-vug pore space. For example, moldic separate vugs will be saturated with oil, whereas microporous grains will be saturated with water. The third category is touching-vug pore space, which is vuggy pore space that is interconnected on a reservoir scale. The engineering parameters for this category are related to three diagenetic and tectonic factors.

  16. Animal Models of Leptospirosis: Of Mice and Hamsters

    PubMed Central

    Gomes-Solecki, Maria; Santecchia, Ignacio; Werts, Catherine

    2017-01-01

    Pathogenic Leptospira sp. are spirochetal bacteria responsible for leptospirosis, an emerging worldwide zoonosis. These spirochetes are very successful pathogens that infect a wide range of hosts such as fish, reptiles, birds, marsupials, and mammals. Transmission occurs when chronically infected animals excrete live bacteria in their urine, contaminating the environment. Leptospira sp. enter their hosts through damaged skin and mucosa. Chronically infected rats and mice are asymptomatic and are considered as important reservoirs of the disease. Infected humans may develop either a flu-like, usually mild illness with or without chronic asymptotic renal colonization, or a severe acute disease with kidney, liver, and heart failure, potentially leading to death. Leptospirosis is an economic burden on society due to health-care costs related to elevated morbidity of humans and loss of animals of agricultural interest. There are no effective vaccines against leptospirosis. Leptospira sp. are difficult to genetically manipulate which delays the pace of research progress. In this review, we discuss in an historical perspective how animal models have contributed to further our knowledge of leptospirosis. Hamsters, guinea pigs, and gerbils have been instrumental to study the pathophysiology of acute lethal leptospirosis and the Leptospira sp. genes involved in virulence. Chronic renal colonization has been mostly studied using experimentally infected rats. A special emphasis will be placed on mouse models, long thought to be irrelevant since they survive lethal infection. However, mice have recently been shown to be good models of sublethal infection leading to chronic colonization. Furthermore, congenic and transgenic mice have proven essential to study how innate immune cells interact with the pathogen and to understand the role of the toll-like receptor 4, which is important to control Leptospira sp. load and disease. The use of inbred and transgenic mouse models opens

  17. Toxoplasma gondii infection in meat animals from Africa: Systematic review and meta-analysis of sero-epidemiological studies

    PubMed Central

    Tonouhewa, Aretas Babatoundé Nounnagnon; Akpo, Yao; Sessou, Philippe; Adoligbe, Camus; Yessinou, Eric; Hounmanou, Yaovi Gildas; Assogba, Marc Napoléon; Youssao, Issaka; Farougou, Souaïbou

    2017-01-01

    Aim: Toxoplasma gondii is an ubiquitous apicomplexan parasite which causes toxoplasmosis in humans and animals. Felids especially cats are definitive hosts and almost all warm-blooded mammals, including livestock and human can serve as intermediate hosts. Food animals can be reservoirs for T. gondii and act as one of the sources for parasite transmission to humans. The objective of this study is to collect serological data on the prevalence of anti-T. gondii antibody, and risk factors for certain food animals from Africa to provide a quantitative estimate of T. gondii infection among these species from different African countries. Materials and Methods: Four databases were used to search seroepidemiological data on the prevalence of anti-T. gondii antibody in food animals between 1969 and 2016 from African countries. The search focused on data obtained by serologic test in food animals and meta-analyses were performed per species. Results: A total of 30,742 individual samples from 24 countries, described in 68 articles were studied. The overall estimated prevalence for toxoplasmosis in chicken, camel, cattle, sheep, goat, pig were 37.4% (29.2-46.0%), 36% (18-56%), 12% (8-17%), 26.1% (17.0-37.0%), 22.9% (12.3-36.0%), and 26.0% (20-32.0%), respectively. Moreover, major risk factor of infection was age, farming system, and farm location. Conclusions: A significant variation in the seroepidemiological data was observed within each species and country. The results can aid in an updated epidemiological analysis but also can be used as an important input in quantitative microbial risk assessment models. Further studies are required for a better and continual evaluation of the occurrence of this zoonotic infection. PMID:28344403

  18. Though not reservoirs, dogs might transmit Leptospira in New Caledonia.

    PubMed

    Gay, Noellie; Soupé-Gilbert, Marie-Estelle; Goarant, Cyrille

    2014-04-17

    Leptospira has been a major public health concern in New Caledonia for decades. However, few multidisciplinary studies addressing the zoonotic pattern of this disease were conducted so far. Here, pig, deer and dog samples were collected. Analyses were performed using molecular detection and genotyping. Serological analyses were also performed for dogs. Our results suggest that deer are a reservoir of L. borgpetersenii Hardjobovis and pigs a reservoir of L. interrogans Pomona. Interestingly, 4.4% of dogs were renal carriers of Leptospira. In dog populations, MAT results confirmed the circulation of the same Leptospira serogroups involved in human cases. Even if not reservoirs, dogs might be of significance in human contamination by making an epidemiological link between wild or feral reservoirs and humans. Dogs could bring pathogens back home, shedding Leptospira via their urine and in turn increasing the risk of human contamination. We propose to consider dog as a vector, particularly in rural areas where seroprevalence is significantly higher than urban areas. Our results highlight the importance of animal health in improving leptospirosis prevention in a One Health approach.

  19. Though not Reservoirs, Dogs might Transmit Leptospira in New Caledonia

    PubMed Central

    Gay, Noellie; Soupé-Gilbert, Marie-Estelle; Goarant, Cyrille

    2014-01-01

    Leptospira has been a major public health concern in New Caledonia for decades. However, few multidisciplinary studies addressing the zoonotic pattern of this disease were conducted so far. Here, pig, deer and dog samples were collected. Analyses were performed using molecular detection and genotyping. Serological analyses were also performed for dogs. Our results suggest that deer are a reservoir of L. borgpetersenii Hardjobovis and pigs a reservoir of L. interrogans Pomona. Interestingly, 4.4% of dogs were renal carriers of Leptospira. In dog populations, MAT results confirmed the circulation of the same Leptospira serogroups involved in human cases. Even if not reservoirs, dogs might be of significance in human contamination by making an epidemiological link between wild or feral reservoirs and humans. Dogs could bring pathogens back home, shedding Leptospira via their urine and in turn increasing the risk of human contamination. We propose to consider dog as a vector, particularly in rural areas where seroprevalence is significantly higher than urban areas. Our results highlight the importance of animal health in improving leptospirosis prevention in a One Health approach. PMID:24747539

  20. An Acute Multispecies Episode of Sheep-Associated Malignant Catarrhal Fever in Captive Wild Animals in an Italian Zoo.

    PubMed

    Frontoso, R; Autorino, G L; Friedrich, K G; Li, H; Eleni, C; Cocumelli, C; Di Cerbo, P; Manna, G; Scicluna, M T

    2016-12-01

    In July 2011, in a zoological garden in Rome, Italy, malignant catarrhal fever (MCF), a fatal, systemic disease of Artiodactyla, was suspected on the basis of neurological signs and gross lesions observed in a banteng, the first animal to die of this infection. An MCF type-specific PCR with subsequent sequencing of the PCR amplicon confirmed the aetiological agent as ovine herpesvirus-2 (OvHV-2). Biological samples were collected from the dead animals for gross, histological, bacteriological, virological and serological examinations. An epidemiological investigation was conducted to identify the source of the outbreak, as further deaths due to OvHV-2 still occurred after the removal of the acknowledged reservoirs, domestic sheep and goats. For this purpose, samples from other susceptible species and reservoir hosts were collected for virological and serological analysis. In conjunction, a retrospective sero-investigation was conducted on sera collected between 1999 and 2010 from some of the species involved in the present episode. In total, 11 animals belonging to four different species (banteng, Himalayan tahr, Nile lechwe and sika deer) died between July 2011 and October 2012. The severe gross and histological lesions were consistent with the disease, namely haemorrhages and congestion of several organs as well as lymphoid cell infiltrates and vasculitis of varying severity. The virological tests confirmed that all animals had died of sheep-associated MCF. The investigation indicated that the OvHV-2 infection could have been due to the arrival of sheep in the petting zoo, with cases commencing after first lambing and subsequent shedding of virus. This was also supported by the serological retrospective study that indicated limited previous MCF virus circulation. Further MCF cases that occurred even after the removal of the domestic sheep and goats were attributed to the mouflon. This episode confirms the importance of biosecurity measures in zoos, which house MCF

  1. Nontoxigenic tox-bearing Corynebacterium ulcerans Infection among Game Animals, Germany

    PubMed Central

    Kutzer, Peter; Peters, Martin; Sing, Andreas; Contzen, Matthias; Rau, Jörg

    2014-01-01

    Corynebacterium ulcerans may cause diphtheria in humans and caseous lymphadenitis in animals. We isolated nontoxigenic tox-bearing C. ulcerans from 13 game animals in Germany. Our results indicate a role for game animals as reservoirs for zoonotic C. ulcerans. PMID:24572455

  2. Models and approaches to dissect host-symbiont specificity.

    PubMed

    Mandel, Mark J

    2010-11-01

    Animals are symbiotic superorganisms, composed of eukaryotic cells and specific microbial residents that perform essential functions for their host. As humans, we are beginning to appreciate the diversity and function of our own microbiota, but model systems are leading the field in illustrating the molecular mechanisms that allow specific relationships to be recapitulated during each host generation. This review focuses on models in which genetic screens, coupled with genomics, imaging, phylogenetics and population biology, have begun to allow a remarkably detailed investigation into the molecular dissection of the evolution of host specificity in animal symbionts.

  3. Unconventional Reservoirs: Ideas to Commercialization

    NASA Astrophysics Data System (ADS)

    Tinker, S. W.

    2015-12-01

    There is no shortage of coal, oil, and natural gas in the world. What are sometimes in short supply are fresh ideas. Scientific innovation combined with continued advances in drilling and completion technology revitalized the natural gas industry in North America by making production from shale economic. Similar advances are now happening in shale oil. The convergence of ideas and technology has created a commercial environment in which unconventional reservoirs could supply natural gas to the North American consumer for 50 years or more. And, although not as far along in terms of resource development, oil from the Eagle Ford and Bakken Shales and the oil sands in Alberta could have a similar impact. Without advanced horizontal drilling, geosteering, staged hydraulic-fracture stimulation, synthetic and natural proppants, evolution of hydraulic fluid chemistry, and high-end monitoring and simulation, many of these plays would not exist. Yet drilling and completion technology cannot stand alone. Also required for success are creative thinking, favorable economics, and a tolerance for risk by operators. Current understanding and completion practices will leave upwards of 80% of oil and natural gas in the shale reservoirs. The opportunity to enhance recovery through advanced reservoir understanding and imaging, as well as through recompletions and infill drilling, is considerable. The path from ideas to commercialization will continue to provide economic results in unconventional reservoirs.

  4. Prevention of Reservoir Interior Discoloration

    SciTech Connect

    Arnold, K.F.

    2001-04-03

    Contamination is anathema in reservoir production. Some of the contamination is a result of welding and some appears after welding but existed before. Oxygen was documented to be a major contributor to discoloration in welding. This study demonstrates that it can be controlled and that some of the informal cleaning processes contribute to contamination.

  5. The panorama of animal leptospirosis in Rio de Janeiro, Brazil, regarding the seroepidemiology of the infection in tropical regions

    PubMed Central

    2013-01-01

    Background Leptospirosis is an important disease caused by various serovars of Leptospira sp. It can affect humans as well as domestic and wild animals; therefore, it has importance for public health, animal production, and wild species. The aim of this paper is to discuss the epidemiology of animal leptospirosis in Rio de Janeiro, Brazil, as a possible model for other tropical regions. In several studies conducted in the last 20 years, a total of 47 rats, 120 dogs, 875 cows, 695 horses, 1,343 goats, 308 sheep and 351 pigs from all regions of the state, in addition to 107 wild mammals and 73 golden-lion tamarins were tested (MAT) for anti-Leptospira antibodies. Results Seroreactivity was frequent in all studied species, confirming that the infection is endemic in Rio de Janeiro. Serogroups Icterohaemorrhagiae and Sejroe were the most prevalent in urban and rural scenarios, respectively. This paper reviews the current knowledge on animal leptospirosis in Rio de Janeiro and describes important differences between urban versus rural cycles of the infection in various species. Conclusion Identification of the prevailing serogroups and their reservoirs is essential for understanding agent-host-environment interactions under tropical conditions. PMID:24289165

  6. Bottlenecks in domestic animal populations can facilitate the emergence of Trypanosoma cruzi, the aetiological agent of Chagas disease

    PubMed Central

    Levy, Michael Z.; Tustin, Aaron; Castillo-Neyra, Ricardo; Mabud, Tarub S.; Levy, Katelyn; Barbu, Corentin M.; Quispe-Machaca, Victor R.; Ancca-Juarez, Jenny; Borrini-Mayori, Katty; Naquira-Velarde, Cesar; Ostfeld, Richard S.

    2015-01-01

    Faeces-mediated transmission of Trypanosoma cruzi (the aetiological agent of Chagas disease) by triatomine insects is extremely inefficient. Still, the parasite emerges frequently, and has infected millions of people and domestic animals. We synthesize here the results of field and laboratory studies of T. cruzi transmission conducted in and around Arequipa, Peru. We document the repeated occurrence of large colonies of triatomine bugs (more than 1000) with very high infection prevalence (more than 85%). By inoculating guinea pigs, an important reservoir of T. cruzi in Peru, and feeding triatomine bugs on them weekly, we demonstrate that, while most animals quickly control parasitaemia, a subset of animals remains highly infectious to vectors for many months. However, we argue that the presence of these persistently infectious hosts is insufficient to explain the observed prevalence of T. cruzi in vector colonies. We posit that seasonal rains, leading to a fluctuation in the price of guinea pig food (alfalfa), leading to annual guinea pig roasts, leading to a concentration of vectors on a small subpopulation of animals maintained for reproduction, can propel T. cruzi through vector colonies and create a considerable force of infection for a pathogen whose transmission might otherwise fizzle out. PMID:26085582

  7. Bottlenecks in domestic animal populations can facilitate the emergence of Trypanosoma cruzi, the aetiological agent of Chagas disease.

    PubMed

    Levy, Michael Z; Tustin, Aaron; Castillo-Neyra, Ricardo; Mabud, Tarub S; Levy, Katelyn; Barbu, Corentin M; Quispe-Machaca, Victor R; Ancca-Juarez, Jenny; Borrini-Mayori, Katty; Naquira-Velarde, Cesar; Ostfeld, Richard S

    2015-07-07

    Faeces-mediated transmission of Trypanosoma cruzi (the aetiological agent of Chagas disease) by triatomine insects is extremely inefficient. Still, the parasite emerges frequently, and has infected millions of people and domestic animals. We synthesize here the results of field and laboratory studies of T. cruzi transmission conducted in and around Arequipa, Peru. We document the repeated occurrence of large colonies of triatomine bugs (more than 1000) with very high infection prevalence (more than 85%). By inoculating guinea pigs, an important reservoir of T. cruzi in Peru, and feeding triatomine bugs on them weekly, we demonstrate that, while most animals quickly control parasitaemia, a subset of animals remains highly infectious to vectors for many months. However, we argue that the presence of these persistently infectious hosts is insufficient to explain the observed prevalence of T. cruzi in vector colonies. We posit that seasonal rains, leading to a fluctuation in the price of guinea pig food (alfalfa), leading to annual guinea pig roasts, leading to a concentration of vectors on a small subpopulation of animals maintained for reproduction, can propel T. cruzi through vector colonies and create a considerable force of infection for a pathogen whose transmission might otherwise fizzle out.

  8. Hydrodynamics of coalbed methane reservoirs in the Black Warrior Basin: Key to understanding reservoir performance and environmental issues

    USGS Publications Warehouse

    Pashin, J.C.

    2007-01-01

    The Black Warrior Basin of the southeastern United States hosts one of the world's most prolific and long-lived coalbed methane plays, and the wealth of experience in this basin provides insight into the relationships among basin hydrology, production performance, and environmental issues. Along the southeast margin of the basin, meteoric recharge of reservoir coal beds exposed in an upturned fold limb exerts a strong control on water chemistry, reservoir pressure, and production performance. Fresh-water plumes containing Na-HCO3 waters with low TDS content extend from the structurally upturned basin margin into the interior of the basin. Northwest of the plumes, coal beds contain Na-Cl waters with moderate to high-TDS content. Carbon isotope data from produced gas and mineral cements suggest that the fresh-water plumes have been the site of significant bacterial activity and that the coalbed methane reservoirs contain a mixture of thermogenic and late-stage biogenic gases. Water produced from the fresh-water plumes may be disposed safely at the surface, whereas underground injection has been used locally to dispose of highly saline water. Wells in areas that had normal hydrostatic reservoir pressure prior to development tend to produce large volumes of water and may take up to 4 a to reach peak gas production. In contrast, wells drilled in naturally underpressured areas distal to the fresh-water plumes typically produce little water and achieve peak gas rates during the first year of production. Environmental debate has focused largely on issues associated with hydrologic communication between deep reservoir coal beds and shallow aquifers. In the coalbed methane fields of the Black Warrior Basin, a broad range of geologic evidence suggests that flow is effectively confined within coal and that the thick intervals of marine shale separating coal zones limit cross-formational flow. ?? 2007 Elsevier Ltd. All rights reserved.

  9. ERTS-1 study of reservoirs in Kansas.

    NASA Technical Reports Server (NTRS)

    Yarger, H. L.; James, G. W.; Magnuson, L. M.; Coiner, J. C.; Mccauley, J. R.; Marzolf, G. R.

    1973-01-01

    Single pass coverage over Cedar Bluff, Webster, Tuttle Creek, Milford, and Council Groves reservoirs is analyzed. The long-range goal of the study is to test the feasibility of monitoring reservoirs by satellite. It is hoped that results may eventually help to optimize reservoir management for use in flood control, agriculture, urban areas, and recreation. ERTS-1 imagery promises to be a very useful tool for studying reservoir turbidity patterns. Initial coverage indicates a strong qualitative correlation between film density and turbidity.

  10. Reservoir System Analysis for Water Quality.

    DTIC Science & Technology

    1984-08-01

    reservoirs on flows and damages in the system. The program should also be useful In selecting the 2 PHASE Z- 1979 SINGLE RESERVOIR SIMULATION FOR WATER...TEMPERATURE PHASE H- 1980 TWO RESERVOIR SIMULATION FOR WATER TEMPERATURE AND SEVEN CONSTITUENTS 1981 FIELD TESTING AND MINOR MODIFICATIONS PHASE M- 1982...TEN RESERVOIR SIMULATION FOR WATER TEMPERATURE AND . TAB SEVEN CONSTITUENTS 1P.IX Ot1Oun4 ___ ___ __ __ ___ __ ___ __ ___ _ .zt ltl@a’tlo@ . 113

  11. Amplitude various angles (AVA) phenomena in thin layer reservoir: Case study of various reservoirs

    SciTech Connect

    Nurhandoko, Bagus Endar B. E-mail: bagusnur@rock-fluid.com; Susilowati E-mail: bagusnur@rock-fluid.com

    2015-04-16

    Amplitude various offset is widely used in petroleum exploration as well as in petroleum development field. Generally, phenomenon of amplitude in various angles assumes reservoir’s layer is quite thick. It also means that the wave is assumed as a very high frequency. But, in natural condition, the seismic wave is band limited and has quite low frequency. Therefore, topic about amplitude various angles in thin layer reservoir as well as low frequency assumption is important to be considered. Thin layer reservoir means the thickness of reservoir is about or less than quarter of wavelength. In this paper, I studied about the reflection phenomena in elastic wave which considering interference from thin layer reservoir and transmission wave. I applied Zoeppritz equation for modeling reflected wave of top reservoir, reflected wave of bottom reservoir, and also transmission elastic wave of reservoir. Results show that the phenomena of AVA in thin layer reservoir are frequency dependent. Thin layer reservoir causes interference between reflected wave of top reservoir and reflected wave of bottom reservoir. These phenomena are frequently neglected, however, in real practices. Even though, the impact of inattention in interference phenomena caused by thin layer in AVA may cause inaccurate reservoir characterization. The relation between classes of AVA reservoir and reservoir’s character are different when effect of ones in thin reservoir and ones in thick reservoir are compared. In this paper, I present some AVA phenomena including its cross plot in various thin reservoir types based on some rock physics data of Indonesia.

  12. Tenth workshop on geothermal reservoir engineering: proceedings

    SciTech Connect

    Not Available

    1985-01-22

    The workshop contains presentations in the following areas: (1) reservoir engineering research; (2) field development; (3) vapor-dominated systems; (4) the Geysers thermal area; (5) well test analysis; (6) production engineering; (7) reservoir evaluation; (8) geochemistry and injection; (9) numerical simulation; and (10) reservoir physics. (ACR)

  13. Reservoir System Regulation for Water Quality Control.

    DTIC Science & Technology

    1983-03-01

    Davis, California 95616. [PHASE I!- 1979 SINGLE RESERVOIR SIMULATION FOR WATER TEMPERATURE PHASE 31- 1980 TWO RESERVOIR SIMULATION FOR WATER TEMPERATURE...AND SEVEN CONSTITUENTS 1981 FIELD TESTING AND MINOR MODIFICATIONS ’IFI PHASE 3nm- 1982 TEN RESERVOIR SIMULATION FOR WATER TEMPERATURE AND SEVEN

  14. 49 CFR 236.792 - Reservoir, equalizing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Reservoir, equalizing. 236.792 Section 236.792 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Reservoir, equalizing. An air reservoir connected with and adding volume to the top portion of...

  15. 49 CFR 236.792 - Reservoir, equalizing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Reservoir, equalizing. 236.792 Section 236.792 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Reservoir, equalizing. An air reservoir connected with and adding volume to the top portion of...

  16. 49 CFR 236.792 - Reservoir, equalizing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Reservoir, equalizing. 236.792 Section 236.792 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Reservoir, equalizing. An air reservoir connected with and adding volume to the top portion of...

  17. 49 CFR 236.792 - Reservoir, equalizing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Reservoir, equalizing. 236.792 Section 236.792 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Reservoir, equalizing. An air reservoir connected with and adding volume to the top portion of...

  18. 49 CFR 236.792 - Reservoir, equalizing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Reservoir, equalizing. 236.792 Section 236.792 Transportation Other Regulations Relating to Transportation (Continued) FEDERAL RAILROAD ADMINISTRATION... Reservoir, equalizing. An air reservoir connected with and adding volume to the top portion of...

  19. Ekofisk reservoir voidage and seabed subsidence

    SciTech Connect

    Mes, M.J. )

    1990-11-01

    Field data describing the time lag between Ekofisk subsidence and reservoir voidage are given. A method to discriminate between real subsidence variations and random-data errors and a procedure to derive a contemporary relationship between reservoir voidage and seabed subsidence are presented. At Ekofisk, most subsidence lags reservoir voidage by 2 to 3 months.

  20. 49 CFR 393.50 - Reservoirs required.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... using air or vacuum braking must have either reserve capacity, or a reservoir, that would enable the.... Each service reservoir system on a motor vehicle shall be protected against a loss of air pressure or vacuum due to a failure or leakage in the system between the service reservoir and the source of...

  1. 49 CFR 393.50 - Reservoirs required.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... using air or vacuum braking must have either reserve capacity, or a reservoir, that would enable the.... Each service reservoir system on a motor vehicle shall be protected against a loss of air pressure or vacuum due to a failure or leakage in the system between the service reservoir and the source of...

  2. 49 CFR 393.50 - Reservoirs required.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... using air or vacuum braking must have either reserve capacity, or a reservoir, that would enable the.... Each service reservoir system on a motor vehicle shall be protected against a loss of air pressure or vacuum due to a failure or leakage in the system between the service reservoir and the source of...

  3. 49 CFR 393.50 - Reservoirs required.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... using air or vacuum braking must have either reserve capacity, or a reservoir, that would enable the.... Each service reservoir system on a motor vehicle shall be protected against a loss of air pressure or vacuum due to a failure or leakage in the system between the service reservoir and the source of...

  4. Broad host range plasmids.

    PubMed

    Jain, Aayushi; Srivastava, Preeti

    2013-11-01

    Plasmids are and will remain important cloning vehicles for biotechnology. They have also been associated with the spread of a number of diseases and therefore are a subject of environmental concern. With the advent of sequencing technologies, the database of plasmids is increasing. It will be of immense importance to identify the various bacterial hosts in which the plasmid can replicate. The present review article describes the features that confer broad host range to the plasmids, the molecular basis of plasmid host range evolution, and applications in recombinant DNA technology and environment.

  5. Pneumocystis carinii, Toxoplasma gondii, Cytomegalovirus and the Compromised Host

    PubMed Central

    Ryning, Frank W.; Mills, John

    1979-01-01

    Pneumocystis carinii and Toxoplasma gondii are the two major parasitic protozoan pathogens in the immunocompromised host. Both organisms cause latent infection in humans and many animals. Cats are the definitive hosts for toxoplasmosis; the animal vector for pneumocystis (if any) has not been defined. Toxoplasma is an obligate intracellular parasite, whereas the available evidence suggests that Pneumocystis carinii exists primarily extracellularly. In compromised hosts, pneumocystis infection usually involves only lungs, whereas toxoplasma causes a generalized infection with encephalitis being the principal clinical manifestation. Both types of infection are treated with combinations of folate antagonists (trimethoprim or pyrimethamine with sulfonamide). Both parasites are associated with cytomegalovirus infection in immunosuppressed hosts, an association which may be due to symbiosis between parasites, or to an additive immunosuppressive effect of dual infection on the hosts. ImagesFigure 1.Figure 3.Figure 4.Figure 7.Figure 8.Figure 9. PMID:217182

  6. Brucellosis at the animal/ecosystem/human interface at the beginning of the 21st century.

    PubMed

    Godfroid, J; Scholz, H C; Barbier, T; Nicolas, C; Wattiau, P; Fretin, D; Whatmore, A M; Cloeckaert, A; Blasco, J M; Moriyon, I; Saegerman, C; Muma, J B; Al Dahouk, S; Neubauer, H; Letesson, J-J

    2011-11-01

    Following the recent discovery of new Brucella strains from different animal species and from the environment, ten Brucella species are nowadays included in the genus Brucella. Although the intracellular trafficking of Brucella is well described, the strategies developed by Brucella to survive and multiply in phagocytic and non-phagocytic cells, particularly to access nutriments during its intracellular journey, are still largely unknown. Metabolism and virulence of Brucella are now considered to be two sides of the same coin. Mechanisms presiding to the colonization of the pregnant uterus in different animal species are not known. Vaccination is the cornerstone of control programs in livestock and although the S19, RB51 (both in cattle) and Rev 1 (in sheep and goats) vaccines have been successfully used worldwide, they have drawbacks and thus the ideal brucellosis vaccine is still very much awaited. There is no vaccine available for pigs and wildlife. Animal brucellosis control strategies differ in the developed and the developing world. Most emphasis is put on eradication and on risk analysis to avoid the re-introduction of Brucella in the developed world. Information related to the prevalence of brucellosis is still scarce in the developing world and control programs are rarely implemented. Since there is no vaccine available for humans, prevention of human brucellosis relies on its control in the animal reservoir. Brucella is also considered to be an agent to be used in bio- and agroterrorism attacks. At the animal/ecosystem/human interface it is critical to reduce opportunities for Brucella to jump host species as already seen in livestock, wildlife and humans. This task is a challenge for the future in terms of veterinary public health, as for wildlife and ecosystem managers and will need a "One Health" approach to be successful.

  7. Expanding the Entamoeba Universe: New Hosts Yield Novel Ribosomal Lineages.

    PubMed

    Jacob, Alison S; Busby, Eloise J; Levy, Abigail D; Komm, Natasha; Clark, C Graham

    2016-01-01

    Removing the requirement for cell culture has led to a substantial increase in the number of lineages of Entamoeba recognized as distinct. Surveying the range of potential host species for this parasite genus has barely been started and it is clear that additional sampling of the same host in different locations often identifies additional diversity. In this study, using small subunit ribosomal RNA gene sequencing, we identify four new lineages of Entamoeba, including the first report of Entamoeba from an elephant, and extend the host range of some previously described lineages. In addition, examination of microbiome data from a number of host animals suggests that substantial Entamoeba diversity remains to be uncovered.

  8. Different pressure grids for reservoir simulation in heterogeneous reservoirs

    SciTech Connect

    Guerillot, D.R.; Verdiere, S.

    1995-12-31

    Petroleum reservoirs are made of highly heterogeneous rocks. These reservoirs could be described by geostatistical models composed of millions of cells. Currently, fluid flow simulations performed within these media need upscaling (or averaging) techniques. Hence, their results are given by averaging on cells which are much larger than the geological model cells. To overcome this problem, the Dual Mesh Method is proposed here, whose purpose is to solve the pressure equation on a low resolution grid, and then to interpolate pressure over the fine mesh by taking into account small scale heterogeneities of the mediums. The aim of this paper is the interpolation step; its implementation is presented and illustrated in a five-spot pattern for three different rock characteristics.

  9. Vector and reservoir control for preventing leishmaniasis

    PubMed Central

    González, Urbà; Pinart, Mariona; Sinclair, David; Firooz, Alireza; Enk, Claes; Vélez, Ivan D; Esterhuizen, Tonya M; Tristan, Mario; Alvar, Jorge

    2015-01-01

    Background Leishmaniasis is caused by the Leishmania parasite, and transmitted by infected phlebotomine sandflies. Of the two distinct clinical syndromes, cutaneous leishmaniasis (CL) affects the skin and mucous membranes, and visceral leishmaniasis (VL) affects internal organs. Approaches to prevent transmission include vector control by reducing human contact with infected sandflies, and reservoir control, by reducing the number of infected animals. Objectives To assess the effects of vector and reservoir control interventions for cutaneous and for visceral leishmaniasis. Search methods We searched the following databases to 13 January 2015: Cochrane Infectious Diseases Group Specialized Register, CENTRAL, MEDLINE, EMBASE, LILACS and WHOLIS, Web of Science, and RePORTER. We also searched trials registers for ongoing trials. Selection criteria Randomized controlled trials (RCTs) evaluating the effects of vector and reservoir control interventions in leishmaniasis-endemic regions. Data collection and analysis Two review authors independently searched for trials and extracted data from included RCTs. We resolved any disagreements by discussion with a third review author. We assessed the quality of the evidence using the GRADE approach. Main results We included 14 RCTs that evaluated a range of interventions across different settings. The study methods were generally poorly described, and consequently all included trials were judged to be at high or unclear risk of selection and reporting bias. Only seven trials reported clinical outcome data which limits our ability to make broad generalizations to different epidemiological settings and cultures. Cutaneous leishmaniasis One four-arm RCT from Afghanistan compared indoor residual spraying (IRS), insecticide-treated bednets (ITNs), and insecticide-treated bedsheets, with no intervention. Over 15 months follow-up, all three insecticide-based interventions had a lower incidence of CL than the control area (IRS: risk

  10. Discovering potential sources of emerging pathogens: South America is a reservoir of generalist avian blood parasites.

    PubMed

    Moens, Michaël A J; Pérez-Tris, Javier

    2016-01-01

    Generalist pathogens are capable of infecting a wide range of host species, and may pose serious disease emergence threats if accidentally moved outside their native areas. To date little effort has been devoted to identifying geographic areas that may act as reservoirs of generalist pathogens. According to current theory, where host diversity is high, parasite specialisation in one host species may be penalised by reduced host availability, while generalist parasites may benefit from the exploitation of various host species. Therefore natural selection could favor generalist parasites where host diversity is high. Here we explored if, in a highly diverse bird community in Ecuador, a generalist strategy is promoted among local Haemoproteus and Plasmodium blood-borne parasites compared with similar parasite communities throughout the world. We reconstructed the phylogenetic relationships of every parasite lineage in order to understand the evolution of host specificity in this megadiverse area. We found high levels of host generalisation for both parasite genera, and the mean host range of the Haemoproteus community in Ecuador was significantly higher than other parasite communities in other areas outside the Neotropics. Generalist Haemoproteus parasites in this bird community had diverse phylogenetic ancestry, were closely related to specialist parasites and were apparently endemic to the Amazon, showing that different parasites have independently evolved into host generalists in this region. Finally we show that Haemoproteus communities in Ecuador and South America are more generalist than in temperate areas, making this continent a hotspot of generalist Haemoproteus parasites for wild birds.

  11. 49 CFR 229.31 - Main reservoir tests.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 49 Transportation 4 2014-10-01 2014-10-01 false Main reservoir tests. 229.31 Section 229.31... reservoir tests. (a) Before it is placed in service, each main reservoir other than an aluminum reservoir... intervals that do not exceed 736 calendar days, each main reservoir other than an aluminum reservoir...

  12. 49 CFR 229.31 - Main reservoir tests.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 49 Transportation 4 2010-10-01 2010-10-01 false Main reservoir tests. 229.31 Section 229.31... reservoir tests. (a) Before it is placed in service, each main reservoir other than an aluminum reservoir... intervals that do not exceed 736 calendar days, each main reservoir other than an aluminum reservoir...

  13. 49 CFR 229.31 - Main reservoir tests.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 49 Transportation 4 2013-10-01 2013-10-01 false Main reservoir tests. 229.31 Section 229.31... reservoir tests. (a) Before it is placed in service, each main reservoir other than an aluminum reservoir... intervals that do not exceed 736 calendar days, each main reservoir other than an aluminum reservoir...

  14. 49 CFR 229.31 - Main reservoir tests.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 49 Transportation 4 2012-10-01 2012-10-01 false Main reservoir tests. 229.31 Section 229.31... reservoir tests. (a) Before it is placed in service, each main reservoir other than an aluminum reservoir... intervals that do not exceed 736 calendar days, each main reservoir other than an aluminum reservoir...

  15. 49 CFR 229.31 - Main reservoir tests.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 49 Transportation 4 2011-10-01 2011-10-01 false Main reservoir tests. 229.31 Section 229.31... reservoir tests. (a) Before it is placed in service, each main reservoir other than an aluminum reservoir... intervals that do not exceed 736 calendar days, each main reservoir other than an aluminum reservoir...

  16. 4. International reservoir characterization technical conference

    SciTech Connect

    1997-04-01

    This volume contains the Proceedings of the Fourth International Reservoir Characterization Technical Conference held March 2-4, 1997 in Houston, Texas. The theme for the conference was Advances in Reservoir Characterization for Effective Reservoir Management. On March 2, 1997, the DOE Class Workshop kicked off with tutorials by Dr. Steve Begg (BP Exploration) and Dr. Ganesh Thakur (Chevron). Tutorial presentations are not included in these Proceedings but may be available from the authors. The conference consisted of the following topics: data acquisition; reservoir modeling; scaling reservoir properties; and managing uncertainty. Selected papers have been processed separately for inclusion in the Energy Science and Technology database.

  17. Reservoir microseismicity at the Ekofisk Oil Field

    SciTech Connect

    Rutledge, J.T.; Fairbanks, T.D.; Albright, J.N.; Boade, R.R.; Dangerfield, J.; Landa, G.H.

    1994-07-01

    A triaxial, downhole geophone was deployed within the Ekofisk oil reservoir for monitoring ambient microseismicity as a test to determine if microearthquake signals generated from discrete shear failure of the reservoir rock could be detected. The results of the test were positive. During 104 hours of monitoring, 572 discrete events were recorded which have been identified as shear-failure microearthquakes. Reservoir microseismicity was detected at large distances (1000 m) from the monitor borehole and at rates (> 5 events per hour) which may allow practical characterization of the reservoir rock and overburden deformation induced by reservoir pressure changes.

  18. The role of reservoir characterization in the reservoir management process (as reflected in the Department of Energy`s reservoir management demonstration program)

    SciTech Connect

    Fowler, M.L.; Young, M.A.; Madden, M.P.

    1997-08-01

    Optimum reservoir recovery and profitability result from guidance of reservoir practices provided by an effective reservoir management plan. Success in developing the best, most appropriate reservoir management plan requires knowledge and consideration of (1) the reservoir system including rocks, and rock-fluid interactions (i.e., a characterization of the reservoir) as well as wellbores and associated equipment and surface facilities; (2) the technologies available to describe, analyze, and exploit the reservoir; and (3) the business environment under which the plan will be developed and implemented. Reservoir characterization is the essential to gain needed knowledge of the reservoir for reservoir management plan building. Reservoir characterization efforts can be appropriately scaled by considering the reservoir management context under which the plan is being built. Reservoir management plans de-optimize with time as technology and the business environment change or as new reservoir information indicates the reservoir characterization models on which the current plan is based are inadequate. BDM-Oklahoma and the Department of Energy have implemented a program of reservoir management demonstrations to encourage operators with limited resources and experience to learn, implement, and disperse sound reservoir management techniques through cooperative research and development projects whose objectives are to develop reservoir management plans. In each of the three projects currently underway, careful attention to reservoir management context assures a reservoir characterization approach that is sufficient, but not in excess of what is necessary, to devise and implement an effective reservoir management plan.

  19. New Hosts of The Lassa Virus

    PubMed Central

    Olayemi, Ayodeji; Cadar, Daniel; Magassouba, N’Faly; Obadare, Adeoba; Kourouma, Fode; Oyeyiola, Akinlabi; Fasogbon, Samuel; Igbokwe, Joseph; Rieger, Toni; Bockholt, Sabrina; Jérôme, Hanna; Schmidt-Chanasit, Jonas; Garigliany, Mutien; Lorenzen, Stephan; Igbahenah, Felix; Fichet, Jean-Nicolas; Ortsega, Daniel; Omilabu, Sunday; Günther, Stephan; Fichet-Calvet, Elisabeth

    2016-01-01

    Lassa virus (LASV) causes a deadly haemorrhagic fever in humans, killing several thousand people in West Africa annually. For 40 years, the Natal multimammate rat, Mastomys natalensis, has been assumed to be the sole host of LASV. We found evidence that LASV is also hosted by other rodent species: the African wood mouse Hylomyscus pamfi in Nigeria, and the Guinea multimammate mouse Mastomys erythroleucus in both Nigeria and Guinea. Virus strains from these animals were isolated in the BSL-4 laboratory and fully sequenced. Phylogenetic analyses of viral genes coding for glycoprotein, nucleoprotein, polymerase and matrix protein show that Lassa strains detected in M. erythroleucus belong to lineages III and IV. The strain from H. pamfi clusters close to lineage I (for S gene) and between II & III (for L gene). Discovery of new rodent hosts has implications for LASV evolution and its spread into new areas within West Africa. PMID:27140942

  20. New Hosts of The Lassa Virus.

    PubMed

    Olayemi, Ayodeji; Cadar, Daniel; Magassouba, N'Faly; Obadare, Adeoba; Kourouma, Fode; Oyeyiola, Akinlabi; Fasogbon, Samuel; Igbokwe, Joseph; Rieger, Toni; Bockholt, Sabrina; Jérôme, Hanna; Schmidt-Chanasit, Jonas; Garigliany, Mutien; Lorenzen, Stephan; Igbahenah, Felix; Fichet, Jean-Nicolas; Ortsega, Daniel; Omilabu, Sunday; Günther, Stephan; Fichet-Calvet, Elisabeth

    2016-05-03

    Lassa virus (LASV) causes a deadly haemorrhagic fever in humans, killing several thousand people in West Africa annually. For 40 years, the Natal multimammate rat, Mastomys natalensis, has been assumed to be the sole host of LASV. We found evidence that LASV is also hosted by other rodent species: the African wood mouse Hylomyscus pamfi in Nigeria, and the Guinea multimammate mouse Mastomys erythroleucus in both Nigeria and Guinea. Virus strains from these animals were isolated in the BSL-4 laboratory and fully sequenced. Phylogenetic analyses of viral genes coding for glycoprotein, nucleoprotein, polymerase and matrix protein show that Lassa strains detected in M. erythroleucus belong to lineages III and IV. The strain from H. pamfi clusters close to lineage I (for S gene) and between II &III (for L gene). Discovery of new rodent hosts has implications for LASV evolution and its spread into new areas within West Africa.

  1. Trophic status evaluation of TVA reservoirs

    SciTech Connect

    Placke, J.F.

    1983-10-01

    TVA tributary and mainstem reservoirs show generalized differences in morphometry, hydraulics, nutrient loads, and response to nutrient concentrations. Neither type of reservoir is strictly comparable to the natural lakes on which classical eutrophication studies have been based. The majority of published trophic state indices and standards (e.g., hypolimnetic dissolved oxygen depletion, Secchi depth, areas nutrient loading rates, in-reservoir phosphorus concentrations) are inappropriate for evaluation of some or all TVA reservoirs. No single trophic potential or trophic response variable summarizes the mechanisms and manifestations of eutrophication sufficiently to be used as a sole criterion for judging or regulating TVA reservoir water quality. Relative multivariate trophic state indices were developed for mainstem and tributary reservoirs. Ranking of the mainstem reservoirs is based on chlorophyll, macrophyte coverage, hydraulic retention time, reservoir area less than five feet deep, annual pool elevation drawdown, and Secchi depth. Based on available data, the rank from least eutrophic to most eutrophic is: Pickwick, Kentucky, Chickamauga, Nickajack, Wilson, Fort Loudoun, Watts Bar, Wheeler, and Guntersville Reservoirs. Ranking of the tributary reservoirs is based on chlorophyll, total phosphorus and total nitrogen weighted by the N:P ratio, and bio-available inorganic carbon levels. The rank from least eutrophic to most eutrophic is: Hiwassee, Blue Ridge, Chatuge, Norris and Fontana, Watauga, South Holston, Tims Ford, Cherokee, Douglas, and Boone Reservoirs. 130 references, 18 figures, 30 tables.

  2. Reservoir floodplains support distinct fish assemblages

    USGS Publications Warehouse

    Miranda, Leandro E.; Wigen, S. L.; Dagel, Jonah D.

    2014-01-01

    Reservoirs constructed on floodplain rivers are unique because the upper reaches of the impoundment may include extensive floodplain environments. Moreover, reservoirs that experience large periodic water level fluctuations as part of their operational objectives seasonally inundate and dewater floodplains in their upper reaches, partly mimicking natural inundations of river floodplains. In four flood control reservoirs in Mississippi, USA, we explored the dynamics of connectivity between reservoirs and adjacent floodplains and the characteristics of fish assemblages that develop in reservoir floodplains relative to those that develop in reservoir bays. Although fish species richness in floodplains and bays were similar, species composition differed. Floodplains emphasized fish species largely associated with backwater shallow environments, often resistant to harsh environmental conditions. Conversely, dominant species in bays represented mainly generalists that benefit from the continuous connectivity between the bay and the main reservoir. Floodplains in the study reservoirs provided desirable vegetated habitats at lower water level elevations, earlier in the year, and more frequently than in bays. Inundating dense vegetation in bays requires raising reservoir water levels above the levels required to reach floodplains. Therefore, aside from promoting distinct fish assemblages within reservoirs and helping promote diversity in regulated rivers, reservoir floodplains are valued because they can provide suitable vegetated habitats for fish species at elevations below the normal pool, precluding the need to annually flood upland vegetation that would inevitably be impaired by regular flooding. Published 2013. This article is a U.S. Government work and is in the public domain in the USA.

  3. Are Migratory Animals Superspreaders of Infection?

    PubMed

    Fritzsche McKay, Alexa; Hoye, Bethany J

    2016-08-01

    Migratory animals are simultaneously challenged by the physiological demands of long-distance movements and the need to avoid natural enemies including parasites and pathogens. The potential for animal migrations to disperse pathogens across large geographic areas has prompted a growing body of research investigating the interactions between migration and infection. However, the phenomenon of animal migration is yet to be incorporated into broader theories in disease ecology. Because migrations may expose animals to a greater number and diversity of pathogens, increase contact rates between hosts, and render them more susceptible to infection via changes to immune function, migration has the potential to generate both "superspreader species" and infection "hotspots". However, migration has also been shown to reduce transmission in some species, by facilitating parasite avoidance ("migratory escape") and weeding out infected individuals ("migratory culling"). This symposium was convened in an effort to characterize more broadly the role that animal migrations play in the dynamics of infectious disease, by integrating a range of approaches and scales across host taxa. We began with questions related to within-host processes, focusing on the consequences of nutritional constraints and strenuous movement for individual immune capability, and of parasite infection for movement capacity. We then scaled-up to between-host processes to identify what types, distances, or patterns of host movements are associated with the spread of infectious agents. Finally, we discussed landscape-scale relationships between migration and infectious disease, and how these may be altered as a result of anthropogenic changes to climate and land use. We are just beginning to scratch the surface of the interactions between infection and animal migrations; yet, with so many migrations now under threat, there is an urgent need to develop a holistic understanding of the potential for migrations to

  4. Geostatistics applied to gas reservoirs

    SciTech Connect

    Meunier, G.; Coulomb, C.; Laille, J.P. )

    1989-09-01

    The spatial distribution of many of the physical parameters connected with a gas reservoir is of primary interest to both engineers and geologists throughout the study, development, and operation of a field. It is therefore desirable for the distribution to be capable of statistical interpretation, to have a simple graphical representation, and to allow data to be entered from either two- or three-dimensional grids. To satisfy these needs while dealing with the geographical variables, new methods have been developed under the name geostatistics. This paper describes briefly the theory of geostatistics and its most recent improvements for the specific problem of subsurface description. The external-drift technique has been emphasized in particular, and in addition, four case studies related to gas reservoirs are presented.

  5. Is Giardia a significant pathogen in production animals?

    PubMed

    Geurden, Thomas; Vercruysse, Jozef; Claerebout, Edwin

    2010-01-01

    Although Giardia duodenalis is recognised worldwide as the most important parasitic cause of gastro-intestinal disorder in human patients, the relevance of infection in production animals is prone to debate. Since the 1980s, clinical disease has been associated with giardiasis in production animals, both in natural conditions and in experimental studies. However, most Giardia research is focussed on the relevance of production animals as a reservoir for zoonotic transmission. In this study, the current knowledge on clinical relevance of giardiasis in production animals is reviewed, along with the diagnosis, treatment and control of infection. Furthermore, future research objectives are discussed.

  6. SEISMIC ATTENUATION FOR RESERVOIR CHARACTERIZATION

    SciTech Connect

    Joel Walls; M.T. Taner; Naum Derzhi; Gary Mavko; Jack Dvorkin

    2003-12-01

    We have developed and tested technology for a new type of direct hydrocarbon detection. The method uses inelastic rock properties to greatly enhance the sensitivity of surface seismic methods to the presence of oil and gas saturation. These methods include use of energy absorption, dispersion, and attenuation (Q) along with traditional seismic attributes like velocity, impedance, and AVO. Our approach is to combine three elements: (1) a synthesis of the latest rock physics understanding of how rock inelasticity is related to rock type, pore fluid types, and pore microstructure, (2) synthetic seismic modeling that will help identify the relative contributions of scattering and intrinsic inelasticity to apparent Q attributes, and (3) robust algorithms that extract relative wave attenuation attributes from seismic data. This project provides: (1) Additional petrophysical insight from acquired data; (2) Increased understanding of rock and fluid properties; (3) New techniques to measure reservoir properties that are not currently available; and (4) Provide tools to more accurately describe the reservoir and predict oil location and volumes. These methodologies will improve the industry's ability to predict and quantify oil and gas saturation distribution, and to apply this information through geologic models to enhance reservoir simulation. We have applied for two separate patents relating to work that was completed as part of this project.

  7. Genotypic analyses of Shiga toxin-producing Escherichia coli O157 and non-O157 recovered from feces of domestic animals in rural farms in Mexico

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Shiga toxin-producing Escherichia coli (STEC) is a zoonotic enteric pathogen associated with human gastroenteritis worldwide. Cattle and small ruminants are important animal reservoirs of STEC. The present study investigated animal reservoirs for STEC in small rural farms in the Culiacan Valley, an...

  8. Assessment of the rabbit as a wildlife reservoir of bovine viral diarrhea virus: serological analysis and generation of trans-placentally infected offspring

    PubMed Central

    Grant, Dawn M.; Dagleish, Mark P.; Bachofen, Claudia; Boag, Brian; Deane, David; Percival, Ann; Zadoks, Ruth N.; Russell, George C.

    2015-01-01

    Eradication of bovine viral diarrhea virus (BVDV) is ongoing in many European countries and is based on removal of persistently infected (PI) cattle. In this context, low-level risks, including alternative reservoirs of infection, may become more important as the number of BVDV-free herds increases. Alternative reservoirs include livestock, such as sheep and goats, as well as wildlife, including deer and rabbits. Due to the extensive nature of the beef industry in Scotland, where an eradication program started in 2010, contact between cattle and alternative reservoir hosts is common. Seroprevalence to BVDV in rabbit populations can be high. In addition, rabbits can be infected with BVDV by natural routes, indicating that they could be a wildlife reservoir of infection. We analyzed the potential risk to livestock from rabbit populations in the UK by two approaches. First, ∼260 serum samples from free-ranging wild rabbits in Scotland and northern England were tested for BVDV-specific antibodies by ELISA. Only three samples exhibited low level BVDV-specific reactivity, suggesting that BVDV infection of rabbits was not frequent. Second, rabbits were challenged with BVDV at day 7 or 12 of pregnancy. This did not lead to any clinical signs in the infected animals or obvious increases in abortion or stillbirth in the infected dams. Samples from the dams, placental material and ∼130 offspring were tested by BVDV-specific RT-PCR and antibody ELISA. Positive PCR results in the placentas and in the tissues and body fluids of rabbits up to 10 days old showed that trans-placental infection of rabbits with BVDV had occurred. Many of the offspring had BVDV-specific antibodies. These data support the view that a wildlife reservoir of BVDV in rabbit poses a small but non-zero risk of re-infection for BVDV-free cattle herds. Rabbits are susceptible to infection with BVDV but only a small proportion of free-living rabbits in the UK appear to have been infected. PMID:26441927

  9. [Animal experimentation, animal welfare and scientific research].

    PubMed

    Tal, H

    2013-10-01

    Hundreds of thousands of laboratory animals are being used every year for scientific experiments held in Israel, mostly mice, rats, rabbits, guinea pigs, and a few sheep, cattle, pigs, cats, dogs, and even a few dozen monkeys. In addition to the animals sacrificed to promote scientific research, millions of animals slain every year for other purposes such as meat and fine leather fashion industries. While opening a front against all is an impossible and perhaps an unjustified task, the state of Israel enacted the Animal Welfare (Animal Experimentation) Law (1994). The law aims to regulate scientific animal experiments and to find the appropriate balance between the need to continue to perform animal experiments for the advancement of research and medicine, and at the same time to avoid unnecessary trials and minimize animal suffering. Among other issues the law deals with the phylogenetic scale according to which experimental animals should be selected, experiments for teaching and practicing, and experiments for the cosmetic industry. This article discusses bioethics considerations in animal experiments as well as the criticism on the scientific validity of such experiments. It further deals with the vitality of animal studies and the moral and legal obligation to prevent suffering from laboratory animals.

  10. Introduced Siberian chipmunks (Tamias sibiricus barberi) contribute more to lyme borreliosis risk than native reservoir rodents.

    PubMed

    Marsot, Maud; Chapuis, Jean-Louis; Gasqui, Patrick; Dozières, Anne; Masséglia, Sébastien; Pisanu, Benoit; Ferquel, Elisabeth; Vourc'h, Gwenaël

    2013-01-01

    The variation of the composition in species of host communities can modify the risk of disease transmission. In particular, the introduction of a new host species can increase health threats by adding a new reservoir and/or by amplifying the circulation of either exotic or native pathogens. Lyme borreliosis is a multi-host vector-borne disease caused by bacteria belonging to the Borrelia burgdorferi sensu lato complex. It is transmitted by the bite of hard ticks, especially Ixodes ricinus in Europe. Previous studies showed that the Siberian chipmunk, Tamias sibiricus barberi, an introduced ground squirrel in the Forest of Sénart (near Paris, France) was highly infested by I. ricinus, and consequently infected by B. burgdorferi sl. An index of the contribution of chipmunks to the density of infected questing nymphs on the vegetation (i.e., the acarological risk for humans) was compared to that of bank voles (Myodes glareolus) and of wood mice (Apodemus sylvaticus), two known native and sympatric competent reservoir hosts. Chipmunks produced nearly 8.5 times more infected questing nymphs than voles and mice. Furthermore, they contribute to a higher diversity of B. burgdorferi sl genospecies (B. afzelii, B. burgdorferi sensu stricto and B. garinii). The contribution of chipmunks varied between years and seasons, according to tick availability. As T. s. barberi must be a competent reservoir, it should amplify B. burgdorferi sl infection, hence increasing the risk of Lyme borreliosis in humans.

  11. Introduced Siberian Chipmunks (Tamias sibiricus barberi) Contribute More to Lyme Borreliosis Risk than Native Reservoir Rodents

    PubMed Central

    Marsot, Maud; Chapuis, Jean-Louis; Gasqui, Patrick; Dozières, Anne; Masséglia, Sébastien; Pisanu, Benoit; Ferquel, Elisabeth; Vourc’h, Gwenaël

    2013-01-01

    The variation of the composition in species of host communities can modify the risk of disease transmission. In particular, the introduction of a new host species can increase health threats by adding a new reservoir and/or by amplifying the circulation of either exotic or native pathogens. Lyme borreliosis is a multi-host vector-borne disease caused by bacteria belonging to the Borrelia burgdorferi sensu lato complex. It is transmitted by the bite of hard ticks, especially Ixodes ricinus in Europe. Previous studies showed that the Siberian chipmunk, Tamias sibiricus barberi, an introduced ground squirrel in the Forest of Sénart (near Paris, France) was highly infested by I. ricinus, and consequently infected by B. burgdorferi sl. An index of the contribution of chipmunks to the density of infected questing nymphs on the vegetation (i.e., the acarological risk for humans) was compared to that of bank voles (Myodes glareolus) and of wood mice (Apodemus sylvaticus), two known native and sympatric competent reservoir hosts. Chipmunks produced nearly 8.5 times more infected questing nymphs than voles and mice. Furthermore, they contribute to a higher diversity of B. burgdorferi sl genospecies (B. afzelii, B. burgdorferi sensu stricto and B. garinii). The contribution of chipmunks varied between years and seasons, according to tick availability. As T. s. barberi must be a competent reservoir, it should amplify B. burgdorferi sl infection, hence increasing the risk of Lyme borreliosis in humans. PMID:23383170

  12. Earthquakes and depleted gas reservoirs: which comes first?

    NASA Astrophysics Data System (ADS)

    Mucciarelli, M.; Donda, F.; Valensise, G.

    2015-10-01

    While scientists are paying increasing attention to the seismicity potentially induced by hydrocarbon exploitation, so far, little is known about the reverse problem, i.e. the impact of active faulting and earthquakes on hydrocarbon reservoirs. The 20 and 29 May 2012 earthquakes in Emilia, northern Italy (Mw 6.1 and 6.0), raised concerns among the public for being possibly human-induced, but also shed light on the possible use of gas wells as a marker of the seismogenic potential of an active fold and thrust belt. We compared the location, depth and production history of 455 gas wells drilled along the Ferrara-Romagna arc, a large hydrocarbon reserve in the southeastern Po Plain (northern Italy), with the location of the inferred surface projection of the causative faults of the 2012 Emilia earthquakes and of two pre-instrumental damaging earthquakes. We found that these earthquake sources fall within a cluster of sterile wells, surrounded by productive wells at a few kilometres' distance. Since the geology of the productive and sterile areas is quite similar, we suggest that past earthquakes caused the loss of all natural gas from the potential reservoirs lying above their causative faults. To validate our hypothesis we performed two different statistical tests (binomial and Monte Carlo) on the relative distribution of productive and sterile wells, with respect to seismogenic faults. Our findings have important practical implications: (1) they may allow major seismogenic sources to be singled out within large active thrust systems; (2) they suggest that reservoirs hosted in smaller anticlines are more likely to be intact; and (3) they also suggest that in order to minimize the hazard of triggering significant earthquakes, all new gas storage facilities should use exploited reservoirs rather than sterile hydrocarbon traps or aquifers.

  13. Evaluating Weeds as Hosts of Tomato yellow leaf curl virus.

    PubMed

    Smith, Hugh A; Seijo, Teresa E; Vallad, Gary E; Peres, Natalia A; Druffel, Keri L

    2015-08-01

    Bemisia tabaci (Gennadius) biotype B transmits Tomato yellow leaf curl virus (TYLCV), which affects tomato production globally. Prompt destruction of virus reservoirs is a key component of virus management. Identification of weed hosts of TYLCV will be useful for reducing such reservoirs. The status of weeds as alternate hosts of TYLCV in Florida remains unclear. In greenhouse studies, B. tabaci adults from a colony reared on TYLCV-infected tomato were established in cages containing one of four weeds common to horticultural fields in central and south Florida. Cages containing tomato and cotton were also infested with viruliferous whiteflies as a positive control and negative control, respectively. Whitefly adults and plant tissue were tested periodically over 10 wk for the presence of TYLCV using PCR. After 10 wk, virus-susceptible tomato plants were placed in each cage to determine if whiteflies descended from the original adults were still infective. Results indicate that Bidens alba, Emilia fosbergii, and Raphanus raphanistrum are not hosts of TYLCV, and that Amaranthus retroflexus is a host.

  14. Enemies and turncoats: bovine tuberculosis exposes pathogenic potential of Rift Valley fever virus in a common host, African buffalo (Syncerus caffer).

    PubMed

    Beechler, B R; Manore, C A; Reininghaus, B; O'Neal, D; Gorsich, E E; Ezenwa, V O; Jolles, A E

    2015-04-22

    The ubiquity and importance of parasite co-infections in populations of free-living animals is beginning to be recognized, but few studies have demonstrated differential fitness effects of single infection versus co-infection in free-living populations. We investigated interactions between the emerging bacterial disease bovine tuberculosis (BTB) and the previously existing viral disease Rift Valley fever (RVF) in a competent reservoir host, African buffalo, combining data from a natural outbreak of RVF in captive buffalo at a buffalo breeding facility in 2008 with data collected from a neighbouring free-living herd of African buffalo in Kruger National Park. RVF infection was twice as likely in individual BTB+ buffalo as in BTB- buffalo, which, according to a mathematical model, may increase RVF outbreak size at the population level. In addition, co-infection was associated with a far higher rate of fetal abortion than other infection states. Immune interactions between BTB and RVF may underlie both of these interactions, since animals with BTB had decreased innate immunity and increased pro-inflammatory immune responses. This study is one of the first to demonstrate how the consequences of emerging infections extend beyond direct effects on host health, potentially altering the dynamics and fitness effects of infectious diseases that had previously existed in the ecosystem on free-ranging wildlife populations.

  15. Modern Reservoir Sedimentation Management Techniques with Examples

    NASA Astrophysics Data System (ADS)

    Annandale, G. W.

    2014-12-01

    Implementation of reservoir sedimentation management approaches results in a win-win scenario, it assists in enhancing the environment by preserving river function downstream of dams while concurrently providing opportunities to sustainably manage water resource infrastructure. This paper summarizes the most often used reservoir sedimentation management techniques with examples of where they have been implemented. Three categories can be used to classify these technologies, i.e. catchment management, sediment routing and sediment removal. The objective of catchment management techniques is to minimize the amount of sediment that may discharge into a reservoir, thereby reducing the loss of storage space due to sedimentation. Reservoir routing is a set of techniques that aim at minimizing the amount of sediment that may deposit in a reservoir, thereby maximizing the amount of sediment that may be passed downstream. The third group consists of techniques that may be used to remove previously deposited sediment from reservoirs. The selection of reservoir sedimentation management approaches is site specific and depends on various factors, including dam height, reservoir volume, reservoir length, valley shape, valley slope, sediment type and hydrology. Description of the different reservoir sedimentation management techniques that are used in practice will be accompanied by case studies, including video, illustrating criteria that may be used to determine the potential success of implementing the techniques.

  16. Storage capacity in hot dry rock reservoirs

    DOEpatents

    Brown, D.W.

    1997-11-11

    A method is described for extracting thermal energy, in a cyclic manner, from geologic strata which may be termed hot dry rock. A reservoir comprised of hot fractured rock is established and water or other liquid is passed through the reservoir. The water is heated by the hot rock, recovered from the reservoir, cooled by extraction of heat by means of heat exchange apparatus on the surface, and then re-injected into the reservoir to be heated again. Water is added to the reservoir by means of an injection well and recovered from the reservoir by means of a production well. Water is continuously provided to the reservoir and continuously withdrawn from the reservoir at two different flow rates, a base rate and a peak rate. Increasing water flow from the base rate to the peak rate is accomplished by rapidly decreasing backpressure at the outlet of the production well in order to meet periodic needs for amounts of thermal energy greater than a baseload amount, such as to generate additional electric power to meet peak demands. The rate of flow of water provided to the hot dry rock reservoir is maintained at a value effective to prevent depletion of the liquid inventory of the reservoir. 4 figs.

  17. Longitudinal gradients along a reservoir cascade

    USGS Publications Warehouse

    Miranda, L.E.; Habrat, M.D.; Miyazono, S.

    2008-01-01

    Reservoirs have traditionally been regarded as spatially independent entities rather than as longitudinal segments of a river system that are connected upstream and downstream to the river and other reservoirs. This view has frustrated advancement in reservoir science by impeding adequate organization of available information and by hindering interchanges with allied disciplines that often consider impounded rivers at the basin scale. We analyzed reservoir morphology, water quality, and fish assemblage data collected in 24 reservoirs of the Tennessee River; we wanted to describe longitudinal changes occurring at the scale of the entire reservoir series (i.e., cascade) and to test the hypothesis that fish communities and environmental factors display predictable gradients like those recognized for unimpounded rivers. We used a data set collected over a 7-year period; over 3 million fish representing 94 species were included in the data set. Characteristics such as reservoir mean depth, relative size of the limnetic zone, water retention time, oxygen stratification, thermal stratification, substrate size, and water level fluctuations increased in upstream reservoirs. Conversely, reservoir area, extent of riverine and littoral zones, access to floodplains and associated wetlands, habitat diversity, and nutrient and sediment inputs increased in downstream reservoirs. Upstream reservoirs included few, largely lacustrine, ubiquitous fish taxa that were characteristic of the lentic upper reaches of the basin. Fish species richness increased in a downstream direction from 12 to 67 species/ reservoir as riverine species became more common. Considering impoundments at a basin scale by viewing them as sections in a river or links in a chain may generate insight that is not always available when the impoundments are viewed as isolated entities. Basin-scale variables are rarely controllable but constrain the expression of processes at smaller scales and can facilitate the

  18. Host preferences in host-seeking and blood-fed mosquitoes in Switzerland.

    PubMed

    Schönenberger, A C; Wagner, S; Tuten, H C; Schaffner, F; Torgerson, P; Furrer, S; Mathis, A; Silaghi, C

    2016-03-01

    The avian zoonotic agent for West Nile virus (WNV) can cause neuroinvasive disease in horses and humans and is expanding its range in Europe. Analyses of the risk for transmission to these hosts in non-endemic areas are necessary. Host preferences of mosquitoes (Diptera: Culicidae), the main vectors of WNV, were determined in Switzerland using animal-baited trap (horse, chickens) experiments at a natural and a periurban site. This was undertaken on four occasions during May-September 2014. In addition, the hosts of 505 blood-fed mosquitoes collected in a zoo and in the field were determined. Mosquito data obtained in the animal bait experiments were corrected for host weight and body surface area and by Kleiber's scaling factor. Collections of 11-14 different mosquito species were achieved with these approaches. Statistically significant host preferences were identified in three species in both approaches. The other species showed opportunistic feeding behaviours to varying extents. Specifically, the invasive species Hulecoeteomyia japonica (= Aedes japonicus) was identified for the first time as feeding on avians in nature. Abundance data, spatiotemporal activity and laboratory vector competence for WNV suggested that, in addition to the main WNV vector Culex pipiens, H. japonica and Aedimorphus vexans (= Aedes vexans) are the most likely candidate bridge vectors for WNV transmission in Switzerland.

  19. Animal Talk in Cocopa

    ERIC Educational Resources Information Center

    Langdon, Margaret

    1978-01-01

    This article discusses an abnormal type of speech in the Cocopa language called animal talk, which deals with how humans refer to the communication between humans and animals and between animals themselves. The derivation of animal talk from normal speech and speech of mythical animals is discussed. (NCR)

  20. Neosporosis. Aspects of epidemiology and host immune response.

    PubMed

    Innes, E A; Buxton, D; Maley, S; Wright, S; Marks, J; Esteban, I; Rae, A; Schock, A; Wastling, J

    2000-01-01

    Neospora caninum is a recently recognized protozoan parasite which has been described as causing a neuromuscular paralysis in dogs and is emerging as a major cause of bovine infertility and abortion worldwide. The parasite is known to infect a range of warm blooded animals but the disease predominates in dogs and cattle. It is not yet known if N. caninum can infect and cause disease in people. The dog has recently been identified as the definitive host and the parasite may be transmitted through the ingestion of oocysts or congenitally from mother to fetus. N. caninum is known to infect red foxes (Vulpes vulpes) and coyotes (Canis latrans) and the role of wildlife species as reservoirs of infection requires further investigation. Little is known about the range of parasite genotypes within the environment or the variation in virulence between different strains. RAPD-PCR analysis of geographically distinct bovine and canine isolates has revealed little genetic variation. Epidemiological studies from different areas of the world have investigated the importance of N. caninum as an abortifacient agent and longitudinal studies have shown the high rate (approximately 80%) of congenital transmission within infected herds. Information on the rates of repeat abortion due to neosporosis are less well defined however current estimates put this at 5% suggesting that cattle may develop some form of protective immunity against N. caninum-induced abortion. Diagnosis of the disease is based upon detection of the parasite in the tissues, most commonly using immunohistochemistry with additional information provided by serology. However, although positive fetal serology is a strong indicator of exposure to the parasite, care should be taken in the interpretation of maternal serology. As we understand more about the epidemiology of neosporosis we are also better able to interpret the results of diagnostic tests. The mere presence of the parasite does not necessarily infer that this

  1. Identification of host blood-meal sources and Borrelia in field-collected Ixodes ricinus ticks in north-western Poland.

    PubMed

    Wodecka, Beata; Skotarczak, Bogumila

    2016-01-01

    Forest animals play fundamental roles in the maintenance of Ixodes ricinus and Borrelia species in the forest biotope. To identify the forest vertebrate species that are host for I. ricinus and for the recognition of the reservoirs of Borrelia species, the blood-meal of 325 I. ricinus ticks collected at two forest sites in north-western Poland were analysed. Nested PCR was used to detect polymorphisms in a fragment of the mitochondrial 12S rRNA gene for the identification of the hosts species. The products were digested with the restriction enzymes, a combination that allows the identification of 60 vertebrate species, comprising 17 bird, 4 reptile and 39 mammalian species. Host DNA was detected in 244 (75%) I. ricinus individuals, with the species being detected and classified for 210 (86%) samples. The restriction patterns resulted in the identification of 14 vertebrate species, including 2 species of birds, lizard, badger, rabbit, deer; most of the samples contained DNA from wild boar (Sus scrofa), red fox (Vulpes vulpes), red deer (Cervus elaphus) and roe deer (Capreolus capreolus). Identification of Borrelia species was based on the flaB gene using nested PCR coupled to RFLP. This method allows the identification of all Borrelia species transmitted by I. ricinus in Europe, including B. miyamotoi and 3 genetic variants of B. garinii. In the studied isolates, 2 species belonging to B. burgdorferi sensu lato were identified--B. garinii and B. afzelii, and B. miyamotoi, which are related to relapsing fever borreliae.

  2. Animals, disease, and man: making connections.

    PubMed

    Hardy, Anne

    2003-01-01

    The intricate causal relationships between disease in man and disease in animals first began to be elucidated in the mid-19th century. Although the connections between animal and human disease are now generally understood, individuals as well as societies remain slow to act on this knowledge. This paper examines the gradual recognition of these disease connections and explores the parallel theme of man's reluctance to appreciate the implications of these connections. It identifies factors that have inhibited the realization of the links between disease in man and animals, and discusses several milestones in the scientific elucidation of these links. Beginning with emerging concerns over the relationship between bovine and human tuberculosis in the 1860s, it follows the discovery of insect vectors, animal reservoirs, and the links between animals, influenza, and man. Despite warnings of the potential significance for human disease of patterns of changes in the relationship with animals and the natural world, scientists have continued to treat human and animal health as largely independent disciplines, while historians too have neglected this important aspect of human disease.

  3. Antimicrobial use in food and companion animals.

    PubMed

    Prescott, John F

    2008-12-01

    The vast literature on antimicrobial drug use in animals has expanded considerably recently as the antimicrobial resistance (AMR) crisis in human medicine leads to questions about all usage of antimicrobial drugs, including long-term usage in intensively managed food animals for growth promotion and disease prevention. Attention is also increasingly focusing on antimicrobial use and on bacterial resistance in companion animals, which are in intimate contact with the human population. They may share resistant bacteria with their owners, amplify resistant bacteria acquired from their owners, and act as a reservoir for human infection. Considerable effort is being made to describe the basis of AMR in bacterial pathogens of animals. Documentation of many aspects of use of antimicrobials in animals is, however, generally less developed and only a few countries can describe quantities of drugs used in animals to kg levels annually. In recent years, many national veterinary associations have produced 'prudent use guidelines' to try to improve antimicrobial drug use and decrease resistance, but the impact of guidelines is unknown. Within the evolving global movement for 'antimicrobial stewardship', there is considerable scope to improve many aspects of antimicrobial use in animals, including infection control and reduction of use, with a view to reducing resistance and its spread, and to preserving antimicrobial drugs for the future.

  4. Antibiotics in animal feed and their role in resistance development.

    PubMed

    Wegener, Henrik C

    2003-10-01

    Animals and humans constitute overlapping reservoirs of resistance, and consequently use of antimicrobials in animals can impact on public health. For example, the occurrence of vancomycin-resistant enterococci in food-animals is associated with the use of avoparcin, a glycopeptide antibiotic used as a feed additive for the growth promotion of animals. Vancomycin-resistant enterococci and vancomycin resistance determinants can therefore spread from animals to humans. The bans on avoparcin and other antibiotics as growth promoters in the EU have provided scientists with a unique opportunity to investigate the effects of the withdrawal of a major antimicrobial selective pressure on the occurrence and spread of antimicrobial resistance. The data shows that although the levels of resistance in animals and food, and consequently in humans, has been markedly reduced after the termination of use, the effects on animal health and productivity have been very minor.

  5. NASA HOST project overview

    NASA Technical Reports Server (NTRS)

    Sokolowski, Daniel E.

    1989-01-01

    NASA's Hot Section Technology (HOST) program has developed improved analytical models for the aerothermal environment, thermomechanical loading, material behavior, structural response, and service life of aircraft gas turbine engines' hot section components. These models, in conjunction with sophisticated computer codes, can be used in design analyses of critical combustor and turbine elements. Toward these ends, efforts were undertaken in instrumentation, combustion, turbine heat transfer, structural analysis, fatigue-fracture, and surface protection. Attention is presently given to the organization of HOST activities and their specific subject matter.

  6. The epidemiology of cancer in animals.

    PubMed

    Dorn, C R

    1967-12-01

    The principles of epidemiology are applicable to the study of the distribution and determinants of cancer in both human and animal populations. There are many examples of epidemiologic factors (host, environment, agent and time) related to cancer in animals. Certain host characteristics such as age, sex and breed are related to risk of developing cancer. Some environmental influences are illustrated by differences in the geographical distribution of certain types of animal cancer. Aggregations of cancer cases have been reported in herds, families and households. However, the usual distribution of cases in a population does not resemble epidemics typical of infectious diseases. Several factors (radiological, chemical, dietary, parasitic, mechanical, genetic and viral) have been identified as influences that affect the development of animal tumors. Animal species that have been domesticated live longer and consequently malignant disease develops in more of them. Cancer incidence rates now available from data compiled by an animal neoplasm registry in Alameda and Contra Costa counties, California, indicate that some of the frequent sites of cancer in man (skin, breast and the hemic and lymphatic systems) are among the most frequent sites in dogs and cats, man's closest animal associates.

  7. Animal models of henipavirus infection: a review.

    PubMed

    Weingartl, Hana M; Berhane, Yohannes; Czub, Markus

    2009-09-01

    Hendra virus (HeV) and Nipah virus (NiV) form a separate genus Henipavirus within the family Paramyxoviridae, and are classified as biosafety level four pathogens due to their high case fatality rate following human infection and because of the lack of effective vaccines or therapy. Both viruses emerged from their natural reservoir during the last decade of the 20th century, causing severe disease in humans, horses and swine, and infecting a number of other mammalian species. The current review summarises current published data relating to experimental infection of small and large animals, including the natural reservoir species, the Pteropus bat, with HeV or NiV. Susceptibility to infection and virus distribution in the individual species is discussed, along with the pathogenesis, pathological changes, and potential routes of transmission.

  8. Nutrition-based health in animal production.

    PubMed

    Adams, Clifford A

    2006-06-01

    Events such as BSE, foot and mouth disease and avian influenza illustrate the importance of animal health on a global basis. The only practical solution to deal with such problems has usually been mass culling of millions of animals at great effort and expense. Serious consideration needs to be given to nutrition as a practical solution for health maintenance and disease avoidance of animals raised for food. Health or disease derives from a triad of interacting factors; diet-disease agent, diet-host and disease agent-host. Various nutrients and other bioactive feed ingredients, nutricines, directly influence health by inhibiting growth of pathogens or by modulating pathogen virulence. It is possible to transform plant-based feed ingredients to produce vaccines against important diseases and these could be fed directly to animals. Nutrients and nutricines contribute to three major factors important in the diet-host interaction; maintenance of gastrointestinal integrity, support of the immune system and the modulation of oxidative stress. Nutrition-based health is the next challenge in modern animal production and will be important to maintain economic viability and also to satisfy consumer demands in terms of food quality, safety and price. This must be accomplished largely through nutritional strategies making optimum use of both nutrients and nutricines.

  9. Host specificity in parasitic plants—perspectives from mistletoes

    PubMed Central

    Okubamichael, Desale Y.; Griffiths, Megan E.; Ward, David

    2016-01-01

    Host specificity has been investigated for centuries in mistletoes, viruses, insects, parasitoids, lice and flukes, yet it is poorly understood. Reviewing the numerous studies on mistletoe host specificity may contribute to our understanding of these plants and put into context the dynamics at work in root parasitic plants and animal parasites. The mechanisms that determine host specificity in mistletoes are not as well documented and understood as those in other groups of parasites. To rectify this, we synthesized the available literature and analyzed data compiled from herbaria, published monographs and our own field studies in South Africa. As for other groups of parasites, multiple factors influence mistletoe host specificity. Initially, pollination affects gene flow. Subsequently, seed dispersal vectors (birds and marsupials), host abundance and compatibility (genetic, morphological, physiological and chemical), history and environmental conditions affect the interaction of mistletoes and their hosts and determine host specificity. Mistletoe–host network analyses and a geographic mosaic approach combined with long-term monitoring of reciprocal transplant experiments, genetic analyses of confined mistletoe populations and comparative phylogenetic studies could provide further insights to our understanding of host specificity. Some of these approaches have been used to study animal–plant interactions and could be adopted to test and evaluate host specificity in mistletoes at local and larger geographic scales. PMID:27658817

  10. Evolution of trophic transmission in parasites: Why add intermediate hosts?

    USGS Publications Warehouse

    Choisy, Marc; Brown, Sam P.; Lafferty, Kevin D.; Thomas, Frédéric

    2003-01-01

    Although multihost complex life cycles (CLCs) ar